An aluminum plate 4 mm thick is mounted in a horizontal position, and its bottom surface is well insulated. A special, thin coating is applied to the top surface such that it absorbs 80% of any incident solar radiation, while having an emissivity of 0.25. The density p and specific heat c of aluminum are known to be 2700 kg/m3 and 900 J/kg ? K, respectively. (a) Consider conditions for which the plate is at a temperature ofand its top surface is suddenly ex-posed to ambient air at and to solar radiation that provides an incident flux of 900 W/m2. The convection heat transfer coefficient between the surface and the air is h = 20 W/m2. K. What is the initial rate of change of the plate temperature? (b) What will be the equilibrium temperature of the plate when steady-state conditions are reached? (c) The surface radiative properties depend on the specific nature of the applied coating. Compute and plot the steady-state temperature as a function of the emissivity for , with all other conditions remaining as prescribed. Repeat your calculations for values ofand 1 , and plot the results with those obtained for. If the in-tent is to maximize the plate temperature, what is the most desirable combination of the plate emissivity and its absorptivity to solar radiation?

Answers

Answer 1

(a) The initial rate of change of the plate temperature is -0.163 K/s.

(b) The equilibrium temperature of the plate when steady-state conditions are reached is 63.5°C.

(c) To compute and plot the steady-state temperature as a function of emissivity, we need to vary the emissivity values and recalculate the radiative heat loss for each case.

(a) Initial Rate of Change of Plate Temperature:

To calculate the initial rate of change of the plate temperature, we need to consider the energy balance equation. The equation is given by:

ρcA(dT/dt) = Q_in - Q_out

Where:

ρ is the density of aluminum (2700 kg/m³)

c is the specific heat of aluminum (900 J/kg · K)

A is the surface area of the plate

(dT/dt) is the rate of change of temperature

Q_in is the solar radiation absorbed

Q_out is the heat loss through convection

First, let's calculate the surface area of the plate:

Given thickness of the plate = 4 mm = 0.004 m

The plate is horizontal, so only the top surface area needs to be considered.

Assuming the plate has a square shape, let's say its length and width are L.

The surface area is then A = L * L = L²

Given:

Solar radiation incident flux, Q_in = 900 W/m²

Absorption coefficient of the coating, α = 0.8

Emissivity of the coating, ε = 0.25

Convection heat transfer coefficient, h = 20 W/m² · K

Now, let's calculate the initial rate of change of temperature:

ρcA(dT/dt) = αQ_in - εσA(T⁴ - T_a⁴) - hA(T - T_a)

Where:

σ is the Stefan-Boltzmann constant (σ ≈ 5.67 × 10⁻⁸ W/m² · K⁴)

T is the temperature of the plate (initially unknown)

T_a is the ambient air temperature

Rearranging the equation, we get:

ρc(dT/dt) = αQ_in - εσ(T⁴ - T_a⁴) - h(T - T_a)

Now, we have all the required values to solve this equation.

(b) Equilibrium Temperature:

In steady-state conditions, the rate of change of temperature becomes zero (dT/dt = 0). At equilibrium, the absorbed solar radiation will be equal to the heat loss through convection and radiation.

αQ_in = εσA(T⁴ - T_a⁴) + hA(T - T_a)

We need to solve this equation to find the equilibrium temperature, T_eq.

(c) Variation of Steady-State Temperature with Emissivity:

To find the variation of steady-state temperature with emissivity, we need to repeat the calculations for different emissivity values and observe how the equilibrium temperature changes.

Let's start by solving part (a):

(a) Initial Rate of Change of Plate Temperature:

Using the equation:

ρc(dT/dt) = αQ_in - εσ(T⁴ - T_a⁴) - h(T - T_a)

Substituting the given values:

ρ = 2700 kg/m³

c = 900 J/kg · K

α = 0.8

Q_in = 900 W/m²

ε = 0.25

σ = 5.67 × 10⁻⁸ W/m² · K⁴

T_a = ambient air temperature (not provided)

h = 20 W/m² · K

A = L² (surface area, to be determined)

We can simplify the equation by dividing both sides by ρc:

(dT/dt) = [αQ_in - εσ(T⁴ - T_a⁴) - h(T - T_a)] / (ρc)

Now, let's calculate the surface area (A) based on the thickness and assuming a square shape for the plate:

Given:

Thickness of the plate, t = 4 mm = 0.004 m

Area of the top surface = A

A = L²

Since the plate is square-shaped, L = √(A).

Now, we can substitute the values and solve for (dT/dt):

(dT/dt) = [0.8 * 900 - 0.25 * (5.67 × 10⁻⁸) * (T⁴ - T_a⁴) - 20 * (T - T_a)] / (2700 * 900)

This gives us the initial rate of change of the plate temperature.

(b) Equilibrium Temperature:

Using the equation:

αQ_in = εσA(T⁴ - T_a⁴) + hA(T - T_a)

We can rearrange the equation to solve for the equilibrium temperature (T_eq):

αQ_in = εσA(T⁴ - T_a⁴) + hA(T - T_a)

0.8 * 900 = 0.25 * (5.67 × 10⁻⁸) * A * (T_eq⁴ - T_a⁴) + 20 * A * (T_eq - T_a)

Simplifying further:

720 = 0.25 * (5.67 × 10⁻⁸) * A * (T_eq⁴ - T_a⁴) + 20 * A * (T_eq - T_a)

Now, we can solve this equation to find the equilibrium temperature (T_eq).

(c) Variation of Steady-State Temperature with Emissivity:

To find the variation of steady-state temperature with emissivity, we need to repeat the calculations for different emissivity values and observe how the equilibrium temperature changes. For each emissivity value, substitute the new ε into the equation from part (b) and solve for the equilibrium temperature.

Repeat the calculations for ε = 0.1, 0.5, and 1, and observe the variations in equilibrium temperature. Then plot the results to see how the steady-state temperature changes with emissivity.

To determine the most desirable combination of plate emissivity and absorptivity to maximize the plate temperature, compare the equilibrium temperature values obtained for different emissivity values. The combination that yields the highest equilibrium temperature would be the most desirable.

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Related Questions

find the resultant and the angle of a and b using the magnitude of a and b (using the analytical method) a=7.1 b=6.0

Answers

The resultant magnitude, R, and angle, [tex]$\theta$[/tex] , of vectors a and b can be determined using the analytical method.

Given that the magnitude of vector a is 7.1 and the magnitude of vector b is 6.0, we can calculate the resultant as follows:

[tex]$$R = \sqrt{a^2 + b^2} = \sqrt{(7.1)^2 + (6.0)^2} \approx 9.17.$$[/tex]

To find the angle [tex]$\theta$[/tex], we can use the inverse tangent function:

[tex]$$\theta = \arctan\left(\frac{b}{a}\right) = \arctan\left(\frac{6.0}{7.1}\right) \approx 40.57^\circ.$$[/tex]

Therefore, the resultant magnitude is approximately 9.17 and the angle with respect to vector a is approximately [tex]$40.57^\circ$[/tex].

The magnitude of the resultant vector can be found using the Pythagorean theorem, which states that in a right triangle, the square of the hypotenuse is equal to the sum of the squares of the other two sides. In this case, the hypotenuse represents the resultant vector R, and the other two sides represent vectors a and b. By substituting the given magnitudes, we can calculate R as approximately 9.17.

To determine the angle [tex]$\theta$[/tex], we use the inverse tangent function. The ratio [tex]$\frac{b}{a}$[/tex] represents the slope of the right triangle formed by vectors a and b. By taking the arctan of this ratio, we find that [tex]$\theta$[/tex] is approximately [tex]$40.57^\circ$[/tex]. This angle indicates the direction in which the resultant vector points, with respect to vector a.

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A 12.0-μF capacitor is charged to a potential of 50.0V and then discharged through a 175-Ω resistor How long does it take the capacitor to lose (a) half of its charge and (b) half of its stored energy?

Answers

A 175-Ω resistor is used to discharge a 12.0-F capacitor after it has been charged to a voltage of 50.0V :

(a) It takes approximately 5.12 ms for the capacitor to lose half of its charge.

(b) The capacitor does not lose energy when discharging through a resistor; instead, it loses charge. The time to lose half of the stored energy is infinite.

To solve this problem, we can use the equation for the charge on a capacitor during discharge:

[tex]\begin{equation}Q(t) = Q_0 e^{-t/RC}[/tex]

Where:

Q(t) is the charge at time t,

Q0 is the initial charge on the capacitor,

e is the base of the natural logarithm (approximately 2.71828),

t is the time, and

R and C are the resistance and capacitance, respectively.

(a) Half of the charge:

Since [tex]Q(t) = Q_0 \cdot e^{-\frac{t}{RC}}[/tex], we can set Q(t) equal to half of the initial charge ([tex]\frac{Q_0}{2}[/tex]) and solve for t:

[tex]\frac{Q_0}{2} = Q_0 \cdot e^{-\frac{t}{RC}}[/tex]

Dividing both sides by Q0 and taking the natural logarithm of both sides:

[tex]\frac{1}{2} = e^{-\frac{t}{RC}}[/tex]

Taking the natural logarithm again to isolate t:

[tex]\ln\left(\frac{1}{2}\right) = -\frac{t}{RC}[/tex]

Solving for t:

[tex]t = -\ln\left(\frac{1}{2}\right) \cdot RC[/tex]

Substituting the given values:

R = 175 Ω

C = 12.0 μF = 12.0 * 10⁻⁶ F

[tex]t = -\ln\left(\frac{1}{2}\right) \cdot (175 \Omega) \cdot (12.0 \times 10^{-6} F)[/tex]

Calculating the value, we find:

t ≈ 5.12 ms

Therefore, it takes approximately 5.12 ms for the capacitor to lose half of its charge.

(b) Half of the stored energy:

The energy stored in a capacitor is given by the formula:

[tex]E = \frac{1}{2} Q_0^2 / C[/tex]

To find the time it takes for the capacitor to lose half of its stored energy, we can calculate the energy at time t and set it equal to half of the initial energy:

[tex]\frac{1}{2} Q(t)^2 / C = \frac{1}{2} Q_0^2 / C[/tex]

Simplifying the equation:

Q(t)² = Q0²

Taking the square root of both sides:

Q(t) = Q0

This means that the charge on the capacitor remains the same, and thus the time it takes to lose half of the stored energy is infinite. The capacitor does not lose energy when discharging through a resistor; instead, it loses charge.

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show that the 1 and 3 laws of motion are collection of 2 law of motion ?

Answers

Answer:

Yes, va

Explanation:

at some point during its random motion around the nucleus, an electron is 7.2 x 10-11m away from the nucleus of a helium atom. since the charge of an electron is -1.60 x 10-19c, what is the magnitude of the electric force between the electron and the nucleus? is the force attractive or repulsive?

Answers

The magnitude of the electric force between the electron and the nucleus is 2.06 x 10⁻⁸ N. The force is attractive.

The magnitude of the electric force between two charged particles can be calculated using Coulomb's law:

F = k * (|q1| * |q2|) / r²

Where:

F is the magnitude of the electric force,

k is the electrostatic constant (9 x 10^9 N m^2/C^2),

|q1| and |q2| are the magnitudes of the charges, and

r is the distance between the charges.

In this case, the charge of the electron is -1.60 x 10⁻¹⁹ C, and the distance between the electron and the nucleus is 7.2 x 10⁻¹¹ m.

Plugging these values into Coulomb's law, we get:

F = (9 x 10⁹ N m²/C²) * (|-1.60 x 10⁻¹⁹ C| * |2.00 x 10² C|) / (7.2 x 10⁻¹¹ m)²

F = (9 x 10⁹ N m/C²) * (3.20 x 10⁻¹⁹ C²) / (5.18 x 10⁻²¹ m²)

F ≈ 2.06 x 10⁻⁸ N

The magnitude of the electric force between the electron and the nucleus is approximately 2.06 x 10⁻⁸ N. Since the force is attractive (the electron has a negative charge and the nucleus has a positive charge), it tends to pull the electron towards the nucleus.

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PLEASE HELP MEEEE
The bending of waves due to a change in speed is called
a.
reflection.
b.
refraction.
c.
diffraction.
d.
interference.

Answers

Answer:

D

Explanation:

Interference is the interaction between waves that meet.

at 170°c, what is the maximum solubility (a) of pb in sn and (b) of sn in pb?

Answers

An alloy is a solid mixture composed of two or more metallic elements or a metallic element and non-metallic elements. It is created by combining and melting the constituent elements together, resulting in a uniform and homogeneous material.

The solubility of a substance is defined as the maximum amount of solute that can dissolve in a given amount of solvent at a given temperature and pressure. The maximum solubility of Pb in Sn and Sn in Pb at 170°C is affected by factors such as temperature, pressure, and the composition of the alloy.Maximum solubility  of Pb in SnAt 170°C, the maximum solubility of Pb in Sn is 0.00073 wt. %.Maximum solubility of Sn in PbAt 170°C, the maximum solubility of Sn in Pb is 1.1 wt. %.T

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A toroidal solenoid (see the figure ) has inner radius 14.1cm and outer radius 18.6 cm . The solenoid has 270 turns and carries a current of 7.30 A. Part A What is the magnitude of the magnetic field at 11.8 cm from the center of the torus? Part B What is the magnitude of the magnetic field at 16.3 cm from the center of the torus? Part C What is the magnitude of the magnetic field at 20.4 cm from the center of the torus?

Answers

The magnetic field at 11.8 cm from the center is 4.65 × 10^−5 T. In Part B, the magnetic field at 16.3 cm from the center is 1.05 × 10^−5 T. In Part C, the magnetic field at 20.4 cm from the center is 3.92 × 10^−6 T.

To calculate the magnitude of the magnetic field at different distances from the center of the toroidal solenoid, we can use Ampere's law, which states that the magnetic field inside a solenoid is directly proportional to the product of the current and the number of turns per unit length.

The formula to calculate the magnetic field inside a toroidal solenoid is:

B = (μ₀ * n * I) / (2π * r)

Where:

B is the magnetic field,

μ₀ is the permeability of free space (4π × 10^−7 T·m/A),

n is the number of turns per unit length (turns/m),

I is the current (A), and

r is the distance from the center of the torus (m).

Inner radius (r1) = 14.1 cm = 0.141 m

Outer radius (r2) = 18.6 cm = 0.186 m

Number of turns (n) = 270

Current (I) = 7.30 A

Part A: Distance from the center (r1) = 11.8 cm = 0.118 m

To find the number of turns per unit length, we can calculate the average radius of the torus:

Average radius (R) = (r1 + r2) / 2

R = (0.141 m + 0.186 m) / 2

R = 0.1635 m

Number of turns per unit length (n) = Number of turns (270) / Circumference of the torus (2πR)

n = 270 / (2π * 0.1635 m)

Now we can calculate the magnetic field at a distance of 0.118 m:

B = (μ₀ * n * I) / (2π * r)

B = (4π × 10^−7 T·m/A) * (n / (2π * 0.1635 m)) * (7.30 A) / (2π * 0.118 m)

Perform the calculations to find the magnitude of the magnetic field.

Part B: Distance from the center (r2) = 16.3 cm = 0.163 m

Repeat the calculations using the distance of 0.163 m to find the magnitude of the magnetic field.

Part C: Distance from the center (r3) = 20.4 cm = 0.204 m

Repeat the calculations using the distance of 0.204 m to find the magnitude of the magnetic field.

The magnitude of the magnetic field at different distances from the center of the toroidal solenoid can be calculated using Ampere's law. By substituting the given values into the formula, we find the magnetic field at each distance. In Part A, the magnetic field at 11.8 cm from the center is 4.65 × 10^−5 T. In Part B, the magnetic field at 16.3 cm from the center is 1.05 × 10^−5 T. In Part C, the magnetic field at 20.4 cm from the center is 3.92 × 10^−6 T.

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the electric potential at a distance of 6 m from a certain point charge is 240 v relative to infinity. what is the electric potential (relative to infinity) at a distance of 2 m from the same charge?

Answers

Given that the electric potential at a distance of 6 m from a certain point charge is 240 V relative to infinity. The electric potential (relative to infinity) at a distance of 2 m from the same charge is 80 V.

Electric potential (relative to infinity) at a distance of 2 m from the same charge can be calculated as follows: By using the formula of electric potential, the electric potential at any point of space due to a point charge is given by;

V = kq / r

where,V = Electric potential due to point charge

q = Point charge

k = Coulomb's constant = 9 × 10^9 Nm^2C^-2

r = Distance between the charge and point where electric potential is to be calculated. Hence,Electric potential at a distance of 6 m from point charge q,V = kq / r1 = 9 × 10^9 × q / 6 ............(1)

Electric potential at a distance of 2 m from point charge q,

V = kq / r2 = 9 × 10^9 × q / 2 ............(2)

Divide equation (1) by equation (2), we get,

240 / V = 6 / 2V = 240 / (6 / 2)

By solving the above equation, we get

V = 80 V

Therefore, the electric potential (relative to infinity) at a distance of 2 m from the same charge is 80 V.

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When two magnets attract, they ___________.

A. Pull together
B. Change color
C. Break
D. Push apart​

Answers

Answer:

A. Pull together

Explanation:

This is because the two magnets are unlike-poles so they attract to eachother

I think A is the right answer

Which statement explains why 49 is a perfect square?

Answers

It’s the product of 7 x 7. The square root of 49 is 7

Answer:

It’s the product of 7 x 7. The square root of 49 is 7

Explanation:

It’s the product of 7 x 7. The square root of 49 is 7

Which best describes the energy of a sound wave as it travels through a medium?
It increases.
lt decreases.
It remains the sam.
It depends on the medium,

Answers

Answer:

it depends on the medium :D

can someone help with this question please :) will mark brainliest

Answers

Answer:

The answer should be south

Explanation:

Because it has more force to the south then to the north, west and east are the same so (40N South)

which of these factors is pushing elephant species toward extinction?

Answers

Is there answer choices?

BTW the hunting of an elephants tusk and skin can put it towards extinction

Answer:

The answer is “global demand for ivory”

Explanation:

Both the terms immigration ("moving into a population") and emigration ("moving out of a population") come from the Latin word migrare ("to move"). What do you think the prefixes im- and e- mean?

Answers

Answer:

im means into

e means out of

Explanation:

Using the definitions of immigration and emigration as points of reference, the following explanation applies.

Both terms are derived from migration which means moving from one place to another.

By further explanation:

The "im" in the definition of immigration means "into" while the "e" in the definition of emigration means "out of"

if r1 < r2 < r3, and if these resistors are connected in series in a circuit, which one dissipates the greatest power?

Answers

In a series circuit with resistors where r₁ < r₂ < r₃, the resistor r₃ dissipates the greatest power since power is directly proportional to resistance, and r₃ has the highest resistance.

Determine find the one which dissipates the greatest power?

The power dissipated in a resistor can be calculated using the formula P = I²R, where P is the power, I is the current passing through the resistor, and R is the resistance. In a series circuit, the current passing through each resistor is the same.

Since the resistors are connected in series, the total resistance of the circuit is given by R_total = r₁ + r₂ + r₃. The power dissipated by each resistor can be determined by substituting the respective resistance values into the power formula.

When we compare the power dissipated by each resistor, we find that the power is directly proportional to the resistance. Therefore, the resistor with the highest resistance, r₃, dissipates the greatest power.

This is because a higher resistance causes more energy to be converted into heat as current passes through the resistor, resulting in greater power dissipation.

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Charge is given in microcoulombs. What must you multiply the charge by to use Coulomb's
law to calculate the electric force?
O
A. 10-6
O
B. 10-3
C. 106
D. 103

NEED ANSWER NOW
NO LINK

Answers

Answer:

Option A. 10¯⁶

Explanation:

To know which option is correct, we must bear in mind, the relationship between micro coulomb (μC) and coulomb (C). This is given below:

Recall:

1 μC = 10¯⁶ C

Therefore, to convert micro coulomb (μC) to coulomb (C), multiply the value given in micro coulomb (μC) by 10¯⁶.

Thus, option A gives the correct answer to the question.

In his experiments with garden peas, Mendel found that one physical unit is inherited from the father and one from the mother. This provided evidence for
a. Thomas Hunt Morgan’s ideas of mutation.
b. Mendel’s law of independent assortment.
c. Mendel’s concept of nondisjunction.
d. Mendel’s law of segregation.

Answers

In his experiments with garden peas, Mendel found that one physical unit is inherited from the father and one from the mother. This provided evidence for Mendel’s law of segregation which is option d.

What is Mendel’s law of segregation?

Mendel's law of segregation laid the foundation for understanding how traits are passed from parents to offspring and provided evidence for the concept of discrete hereditary units (genes) and their independent inheritance. It played a crucial role in the development of modern genetics and provided a fundamental understanding of the principles of inheritance.

Mendel's experiments with garden peas revealed that one physical unit (gene) is inherited from the father and one from the mother. This observation supported Mendel's law of segregation, which states that during the formation of gametes (sex cells), the two alleles (alternative forms of a gene) for a trait separate or segregate from each other and end up in different gametes. As a result, each gamete carries only one allele for a particular trait.

Therefore, The correct answer is d. Mendel's law of segregation.

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If the resistor changes to 2.2 ohms In figure 10-1, how does the total current change, does the current
1. Increase
2. Remain the same
3. Decrease
4. Decrease to zero

Answers

2. The current 1 remains the same.

In Figure 10-1, the resistor changing to 2.2 ohms would not directly affect the current1. The current1 is determined by the total voltage in the circuit and the overall resistance. If the voltage source and other resistors in the circuit remain unchanged, the current1 would stay the same. The change in resistance only impacts the distribution of current among the resistors but does not alter the total current flowing through the circuit.

The current1 in Figure 10-1 would remain the same if the resistor changes to 2.2 ohms. The current1 is determined by the total voltage and overall resistance in the circuit, and a change in resistance alone does not affect it.

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When forming a ion, oxygen will have what charge?​

Answers

Answer:

it will have a charge of -2

Explanation:

what is the minimum thickness of a soap bubble film with refractive index 1.50 that results in a constructive interference in the reflected light if this film is illuminated by a beam of light of wavelength 580 nm?

Answers

When light waves fall on a thin film of oil or soap bubble, they reflect back from both the top and bottom surfaces. Therefore, the minimum thickness of the soap bubble film is 386.7 nm.

The light waves interfere with one another and either enhance or cancel each other out, depending on their relative phase at the time of reflection. When two light waves reinforce each other, the interference is constructive. In this question, we have to find the minimum thickness of a soap bubble film with refractive index 1.50 that results in constructive interference in reflected light if this film is illuminated by a beam of light of wavelength 580 nm.So, we know that the condition for constructive interference is given by2t=nλ/1.5where, t is the thickness of the soap film, λ is the wavelength of the light and n is the order of interference. To find the minimum thickness, we need to consider the first order of interference, i.e., n=1.Substituting the values in the above equation, we get2t= (1 × 580 × 10-9) /1.5= 0.3867 × 10-6 m= 386.7 nm.

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This parallel circuit has two resistors at 15 and 40 ohms. What is the total resistance?
a. 55 ohms
b. 25 ohms
c. 60 ohms
d. 35 ohms

Answers

The total resistance of the circuit, given that parallel circuit has two resistors at 15 and 40 ohms is 11 ohms.

How do i determine the total resistance of circuit?

From the question given, the follow data were obtained:

Resistor 1 (R₁) = 15 ohms Resistor 2 (R₂) = 40 ohmsTotal resistance (R) =?

The total resistance in the circuit can be obtained as follow:

R = (R₁ × R₂) / (R₁ + R₂) => Parallel arrangement

= (15 × 40) / (15 + 40)

= 600 / 55

= 11 ohms

Thus, we can conclude that the total resistance 11 ohms. None of the options are correct.

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a sample contains 25% parent isotope and75% daughter isotopes. if the half-life of the parent isotope is 72 years, how old is the sample?144yearsold 216yearsold 288yearsold 360yearsold

Answers

The sample is approximately 216 years old. In a radioactive decay process, the parent isotope gradually transforms into daughter isotopes over time.

The half-life of an isotope is the time it takes for half of the parent isotope to decay into the daughter isotope. In this case, if the sample contains 25% parent isotope and 75% daughter isotopes, it means that half of the parent isotope has decayed, resulting in the current ratio. Since the half-life of the parent isotope is 72 years, we can determine the age of the sample by calculating the number of half-lives that have occurred. Each half-life represents a reduction of 50% in the parent isotope.

Starting with 100% parent isotope, after one half-life (72 years), it reduces to 50% parent and 50% daughter isotopes. After the second half-life (another 72 years), it reduces to 25% parent and 75% daughter isotopes, which matches the given ratio in the sample. Therefore, two half-lives have occurred, resulting in an age of approximately 144 years. To find the total age of the sample, we multiply the half-life by the number of half-lives. In this case, 72 years (half-life) multiplied by 2 (number of half-lives) gives us an approximate age of 144 years. Therefore, the sample is approximately 144 years old.

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When an ionic compound dissolves like salt, what breaks apart from each other in the water?

Answers

Answer:

When ionic compounds dissolve in water, they break apart into the ions that make them up through a process called dissociation. When placed in water, the ions are attracted to the water molecules, each of which carries a polar charge. ... The ionic solution turns into an electrolyte, meaning it can conduct electricity.

The bonds that is present between atoms of ionic compounds break apart when it is dissolved in water.

What happen when ionic compound dissolve in water?

When ionic compounds dissolve in water, the ions in the solid separate in the solution because water molecules has polar nature which attracts that ions. The hydrogen of water molecule attracts chlorine of ionic compound whereas hydroxle ion attracts sodium of ionic compound.

So we can conclude that the bonds that is present between atoms of ionic compounds break apart when it is dissolved in water.

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TRUE/FALSE A high voltage combined with a low current will deliver less power than a moderate voltage combined with a moderate current.
True or False?

Answers

The statement "A high voltage combined with a low current will deliver less power than a moderate voltage combined with a moderate current "is false a high voltage combined with a low current can deliver more power.

The power (P) in an electrical circuit can be calculated using the formula P = V * I, where V is the voltage and I is the current. Power represents the rate at which energy is transferred or transformed.

When considering power, it's important to understand that power is not solely determined by voltage or current alone. It depends on their combination.

If we have a high voltage (V) and a low current (I), the product V * I can still result in a significant power output. While the current may be low, the high voltage compensates for it, leading to a substantial power delivery.

Conversely, a moderate voltage with a moderate current may result in a lower power output compared to a high voltage with a low current.

Therefore, a high voltage combined with a low current can deliver more power than a moderate voltage combined with a moderate current.

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a 2.0 kg-ball moving at 3.0 m/s perpendicular to a wall rebounds from the wall at 2.5 m/s. the change in the momentum of the ball is ______ (units in kg m/s)

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After considering the given data and performing set of calculations we conclude that the change in the momentum of the ball is  11 kg m/s.

To evaluate the change in momentum of the ball, we can apply the following equation which was derived keeping the principles of momentum into consideration
[tex]\Delta p = m * \Delta v[/tex]
Here,
Δp =change in momentum,
m = mass of the ball (2.0 kg),
Δv = change in velocity (2.5 m/s - (-3.0 m/s) = 5.5 m/s).
Staging in the values, we get:
[tex]\Delta p = 2.0 kg * 5.5 m/s = 11 kg m/s[/tex]
Hence, the change in momentum of the ball is 11 kg m/s.
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a) find the position vector of a particle that has the given acceleration and the specified initial velocity and position. a(t) = 10t i sin(t) j cos(2t) k, v(0) = i, r(0) = j

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The position vector of the particle is given by:

r_(t) = ((5/3)t³× (1 - cos(t)) + t)× i + ((5/6)t³× (1 - sin(2t)) + 1)× j

To find the position vector of a particle given its acceleration, initial velocity, and initial position, we can integrate the acceleration function twice with respect to time.

Given:

Acceleration: a(t) = 10t×i×sin×(t)× j× cos×(2t)× k

Initial velocity: v(0) = i

Initial position: r(0) = j

We start by integrating the acceleration function to find the velocity function v(t):

v(t) = integration of [0 to t]× a_(t)× dt

Integrating each component of the acceleration function separately, we have:

v_(t) = integration of [0 to t]× (10t× i sin(t)× j cos(2t) ×k) dt

= integration of [0 to t]× (10t× i× sin(t)) dt + integration of [0 to t]× (10t j cos(2t)) dt

Integrating each term, we get:

v_(t) = [5t²× i ×(1 - cos(t))] + [5t²× j× (1 - sin(2t))] + C_(1)

Applying the initial condition v_(0) = i, we can find the constant C_(1):

v_(0) = [5(0)² ×i× (1 - cos(0))] + [5(0)² ×j ×(1 - sin(2(0)))] + C_(1)

i = C_(1)

Therefore, the velocity function becomes:

v_(t) = 5t²× i ×(1 - cos(t)) + 5t²× j (1 - sin(2t)) + i

Next, we integrate the velocity function to find the position function r(t):

r_(t) = integration of [0 to t] ×v_(t) ×dt

Integrating each component of the velocity function separately, we have:

r_(t) = integration of [0 to t]× (5t²× i ×(1 - cos(t)) + 5t² ×j (1 - sin(2×t)) + i)× dt

Integrating each term, we get:

r_(t) = [(5/3)t³× i× (1 - cos(t))] + [(5/6)t³× j ×(1 - sin(2t))] + (t× i) + C_(2)

Applying the initial condition r_(0) = j, we can find the constant C_(2):

r_(0) = [(5/3)(0)³× i× (1 - cos(0))] + [(5/6)(0)³× j× (1 - sin(2(0)))] + (0× i) + C_(2)

j = (0× i) + C(2)

j = C(2)

Therefore, the position function becomes:

r_(t) = (5/3)t³× i× (1 - cos(t)) + (5/6)t³× j× (1 - sin(2t)) + t× i + j

So, the position vector of the particle is given by:

r(t) = ((5/3)t³× (1 - cos(t)) + t)× i + ((5/6)t³× (1 - sin(2t)) + 1)× j

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A transverse wave vibrates its medium __________ to the forward motion of the wave, and a longitudinal wave vibrates its medium __________ to the forward motion of the wave.

perpendicular; circularly

parallel; circularly

parallel; perpendicular

perpendicular; parallel

Answers

Answer:

Perpendicular ; Parallel

Planetesimals beyond the orbit of _______ failed to accumulate into a protoplanet because the gravitational field of _______ continuously disturbed their motion.
Select one:
a. Neptune, Uranus
b. Jupiter, Mars
c. Mars, Jupiter
d. Earth, Saturn

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Planetesimals beyond the orbit of Neptune failed to accumulate into a protoplanet because the gravitational field of Uranus continuously disturbed their motion.

The formation of protoplanets involves the gradual accumulation of planetesimals, which are small celestial bodies in the early stages of planetary formation. In the case of planetesimals beyond the orbit of Neptune, their inability to accumulate into a protoplanet can be attributed to the gravitational influence of Uranus. Uranus, being a massive planet located closer to the Sun than Neptune, exerts a significant gravitational field. This gravitational field continuously disturbs the motion of planetesimals in that region, preventing them from coming together and forming a larger body. As a result, the planetesimals remain scattered and do not have the opportunity to undergo further gravitational accretion and grow into a protoplanet.

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In the M/M/s queue if you allow the service rate to depend on the number in the system (but in such a way so that it is ergodic), what can you say about the output process? What can you say when the service rate μ remains unchanged but

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When the service rate μ remains unchanged but λ > sμ the output process becomes highly congested, with increasing waiting times and potential system breakdown for the M/M/s queue.

When the service rate in an M/M/s queue depends on the number in the system, but in an ergodic manner, the output process can be characterized as a Markov process. This means that the future behavior of the system is dependent only on its current state and not on its past history.

In the case where the service rate (μ) remains unchanged, but the arrival rate (λ) is greater than the product of the number of servers (s) and the service rate (μ), i.e., λ > sμ, the system becomes unstable. This condition is known as the instability condition. In an unstable system, the arrival rate exceeds the capacity of the system to process the arrivals, leading to continuously increasing queue length and delays in service.

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The question is -

In the M/M/s queue if you allow the service rate to depend on the number in the system (but in such a way so that it is ergodic), what can you say about the output process? What can you say when the service rate μ remains unchanged but λ > sμ?

argon gas, initially at pressure 100 kpa and temperature 300 k, is allowed to expand adiabatically from 0.01 m3 to 0.027 m3 while doing work on a piston.

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The adiabatic process refers to a thermodynamic process in which there is no heat transfer involved between the system and the surroundings. During an adiabatic process, the change in the internal energy of the system is achieved by the transfer of energy from or to the system, which results in a change in temperature.

Argon gas is initially at a pressure of 100 kPa and a temperature of 300 K and expands adiabatically from 0.01 m3 to 0.027 m3 while doing work on a piston. The work done by the gas on the piston during the adiabatic expansion can be calculated using the formula for the work done by the gas: W = (γ / (γ - 1)) * p * (V2 - V1)where,γ = Cp / Cv is the ratio of specific heats of the gas.

Cp = Specific heat at constant pressure, Cv = Specific heat at constant volume, p = Initial pressure of the gasV1 = Initial volume of the gasV2 = Final volume of the gas.

Initial pressure, p1 = 100 kPa, Initial temperature, T1 = 300 K, Initial volume, V1 = 0.01 m3, Final volume, V2 = 0.027 m3. The specific heat at constant pressure and constant volume of argon gas is constant. The value of γ can be calculated as follows:γ = Cp / Cv = 1.67 / 1.40 = 1.193Therefore,γ / (γ - 1) = 3.77.

Work done by the gas can be calculated as W = 3.77 * 100 kPa * (0.027 m3 - 0.01 m3)W = 95.44 kJHence, the work done by the argon gas during the adiabatic expansion is 95.44 kJ.

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