Plz help I don’t know what to do

Answer:

3.38m

Explanation:

Given parameters:

Time  = 4s

Acceleration  = 1.3m/s²

Unknown:

Magnitude of the displacement = ?

Solution:

The body starts at rest and the initial velocity is 0m/s. To solve this problem, we have to use the expression below;

    S   = Ut  + [tex]\frac{1}{2}[/tex]at²

 S  = displacement

t is the time

  a is the acceleration

  U is the initial velocity

  V is the final velocity

Insert the parameters and solve;

   S = (0 x 4)  +  [tex]\frac{1}{2}[/tex] x 1.3² x 4  = 3.38m

Answer: The amount of time it takes for half of the material to decay

B. The time needed for half of a sample of radioisotope to decay is the half-life of a radioisotope.

Radioactive decay is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is considered radioactive.

The most common types of decay are alpha decay, beta decay, and gamma decay, all of which involve emitting one or more particles.

The radioactive half-life means, the time required for half the atoms of a particular radioisotope to decay into another isotope.

The half-life of a radioactive isotope is the amount of time it takes for one-half of the radioactive isotope to decay.

The half-life of a specific radioactive isotope is constant; it is unaffected by conditions and is independent of the initial amount of that isotope.
Therefore,

The half-life of a radioisotope is the time needed for half of a sample of radioisotope to decay.

The correct option is B

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Chlorine Cl: 17 protons, 17 electrons, 7 Valence electrons, Nonmetal, Give 3, 14 new electrons, +1, Cl-

Magnesium Mg: 12 protons, 12 electrons, 3 Valence electrons, Metal, Give 2, 10 new electrons, 2-, Mg ^2+

Oxygen O: 8 protons, 8 electrons, 6 Valence electrons, Nonmetal, Give 6, 2 new electrons, -2, 0 ^2-

Nitrogen N: 7 protons, 7 electrons, 5 Valance electrons, Nonmetal, Give 4, 3 new electrons, -3, N ^3-

I really hope this helps :)

Answer:

57°

Explanation:

Etienne Malus discovered the idea of polarization by reflection. If light is incident on a surface at an angle of 57°, the reflected ray is found to be plane polarized.

Hence, with respect to the normal to the interface, light incident at 57° is completely polarized.

Answer:

526.5m

Explanation:

Given parameters:

Acceleration = 3m/s²

Initial velocity  = 21m/s

Final velocity  = 60m/s

Unknown:

Displacement = ?

Solution:

To solve this problem, we apply the right motion equation which is shown below;

     V²  = U²  + 2aS

  V is the final velocity

  U is the initial velocity

  a is the acceleration

 S is the displacement

 Insert the parameters and solve;

    60²  = 21² + 2(3)S

    3600 = 441 + 6S

    3600 - 441  = 6S

    3159  = 6S

       S = 526.5m

Answer:

3rd. outer

Explanation:

they are electropositive have a tendency to give electrons

Answer:

I'm pretty sure that the answer is C. Hope this helps.

Explanation:

Answer:

Answer is A. Under any conditions

Explanation:

Just got it correct on A p e x

Answer:

c

Explanation:

The lamp lights up using electrical power, and so the light bulb heats up.

Answer:a

Explanation:

i took the test

Answer:

B) enough water I agree with what the person under/over me said

Explanation:

Answer:

12s

Explanation:

Given parameters:

Velocity  = 7.5m/s

Distance  = 90m

Unknown:

Time taken  = ?

Solution:

Speed is the rate of distance traveled with time. It is mathematically expressed as;

      Speed  = [tex]\frac{distance}{time}[/tex]

Since the unknown is time;

        Time  = [tex]\frac{distance}{speed}[/tex]  

      Insert the parameters and solve;

  Time  = [tex]\frac{90}{7.5}[/tex]   = 12s

Answer:

Identity versus confusion is the fifth stage of ego according to psychologist Erik Erikson's theory of psychosocial development.

Explanation:This stage occurs during adolescence between the ages of approximately 12 and 18. During this stage, adolescents explore their independence and develop a sense of self.

Answer:

D) autonomy versus shame and doubt

Explanation:

Answer: 2.7

Explanation:

Answer:

ΔP.E = - 588 J

Explanation:

The complete question is as follows:

It is said that Galileo dropped objects off the Leaning Tower of Pisa to determine whether heavy or light objects fall faster. If Galileo had dropped a 5.0-kg cannon ball to the ground from a height of 12 m, what would have been the change in PE of the cannon ball?

Answer: So, in order to calculate the change in Potential Energy of the cannon ball, we will use the general formula of Potential Energy as follows:

ΔP.E = mgΔh

where,

ΔP.E = Change in Potential Energy = ?

m = mass of cannon ball = 5 kg

g = acceleration due to gravity = 9.8 m/s²

Δh = Change in Height of Cannon Ball = Final Height - Initial Height

Δh = 0 m - 12 m = - 12 m

Therefore,

ΔP.E = (5 kg)(9.8 m/s²)(- 12 m)

ΔP.E = - 588 J

Negative sign shows decrease in Potential Energy

Answer:

a = 0.73 m/s²

Explanation:

Considering South direction to be positive and North to be negative. The unbalanced force on bugs bunny will be given as:

Unbalanced Force = Force of Buster - Force of Babs - Friction

Unbalanced Force = 120 N - 50 N - 15 N

Unbalanced Force = 55 N

But, from Newton's Second Law:

Unbalanced Force = ma

55 N = ma

where,

m = mass of Bugs Bunny = 75 kg

a = acceleration of Bugs Bunny = ?

Therefore,

55 N = (75 kg)a

a = 55 N/75 kg

a = 0.73 m/s²

Answer:

a = 0.73 m/s²

Explanation:

-_- im tired -_-

Answer:

a. The initial velocity will decrease until it reaches its final velocity/maximum (which is 0).

b. The acceleration always remain constant.

Explanation:

Nuclear energy is argued to be renewable because it is found in the atoms that make up the earth, does not emit carbon and its use can be made unlimited by the use of technologies.

Answer:

Nuclear energy is a non-renewable energy source that comes from the nucleus of atoms.

Answer:

its y

Explanation:

Answer:

short circuit

Explanation:

A disrupted circuit in which the current bypasses its proper path is a short circuit.

A short circuit is an electrical circuit which allows the electric current to travel along an unintended and uninterrupted path with no or very low electrical impedance in the circuit. This results in an excessive current flow through the electric circuit.

A short circuit is a situation in which there is  faulty connection or damaged wire that causes electric current to travel along the wrong route in the circuit with low or no resistance and damage an electrical device. This may cause serious damage, fire, or even small-scale explosions.

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Answer:

22.4 s

Explanation:

The following data were obtained from the question:

Mass (m) = 75 Kg

Height (h) = 50 ft

Power (P) = 500 W

Acceleration due to gravity (g) = 9.8 m/s²

Time (t) =?

Next, we shall convert 50 ft to metres (m). This can be obtained as follow:

1 ft = 0.3048 m

Therefore,

50 ft = 50 ft × 0.3048 m / 1 ft

50 ft = 15.24 m

Thus, 50 ft is equivalent 15.24 m.

Next, we shall determine the energy used by the student to walk up three flights of stairs. This can be obtained as follow:

Mass (m) = 75 Kg

Height (h) = 15.24 m

Acceleration due to gravity (g) = 9.8 m/s²

Energy (E) =?

E = mgh

E = 75 × 9.8 × 15.24

E = 11201.4 J

Finally, we shall determine the time taken for the student to travel up the three flights of stairs. This can be obtained as follow:

Power (P) = 500 W

Energy (E) = 11201.4 J

Time (t)

Power (P) = Energy (E) / Time (t)

500 = 11201.4 /t

Cross multiply

500 × t = 11201.4

Divide both side by 500

t = 11201.4 /500

t = 22.4 s

Therefore, it will take the student 22.4 s to travel up the three flights of stairs.

The time taken for the student to travel up the three stairs is 22.4 s.

The given parameters;

The gravitational potential energy of the student due to vertical position of the three stairs is calculated as;

[tex]P.E = mgh\\\\P.E = 75 \times 9.8 \times 15.24 \\\\P.E =11,201.4 \ J[/tex]

The time taken for the student to travel up the three stairs is calculated as follows;

[tex]E = Pt\\\\t = \frac{E}{P} \\\\t = \frac{11,201.4}{500} \\\\t = 22.4 \ s[/tex]

Thus, the time taken for the student to travel up the three stairs is 22.4 s.

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Answer:

After 30 minutes, the temperature of the body is: T₁₀ = 311.60 K

After 60 minutes, the temperature of the body is: T₂₀ = 298.18 K

Explanation:

Given that:

[tex]\dfrac{dT}{dt}= K \bigg [ M(t) -T(t)\bigg][/tex]

where;

K = 0.04

M(t) = 293

Then;

[tex]\dfrac{dT}{dt}= 0.04 \bigg [ 293 -T\bigg][/tex]

[tex]\dfrac{dT}{dt}= 11.72 -0.04 \ T[/tex]

Using Euler's Formula;

[tex]T_{n+1} = T_n + hf( t_n, T_n)[/tex]

where;

[tex]f(t_n,T_n) = 11.72 - 0.04 T_n[/tex]

Then;

[tex]T_{n+1} = T_n + 3.0 (11.72-0.04 \ T_n)[/tex]

[tex]T_{n+1} = 0.88T_n + 35.16 \ ---(1)[/tex]

At initial state [tex]t_0[/tex]  (0);  [tex]T_0[/tex] = 360

At t₁ = 3.0 when T₀ = 360

[tex]T_1= 0.88 T_o + 35.16[/tex]

[tex]T_1= 0.88 (360) + 35.16[/tex]

[tex]T_1 = 351.96 \ K[/tex]

At t₂ = 6.0 when T₂ = 0.88T₁ + 35.16

T₂ = 0.88(351.96) + 35.16

T₂ = 344.89 K

At t₃ = 9.0 when T₃ = 0.88T₂ + 35.16

T₃ = 0.88(344.89) + 35.16

T₃ =338.66 K

At t₄ = 12.0 when T₄ = 0.88T₃ + 35.16

T₄ = 0.88(338.66) + 35.16

T₄ = 333.18 K

At  t₅ = 15.0 when T₅ = 0.88T₄ + 35.16

T₅ = 0.88(333.18) + 35.16

T₅ = 328.36 K

At t₆ = 18.0 when T₆ =  0.88T₅ + 35.16

T₆ = 0.88(328.36) + 35.16

T₆ = 324.12 K  

At t₇ = 21.0 when T₇ = 0.88T₆ + 35.16

T₇ = 0.88(324.12) + 35.16

T₇ = 320.39 K

At t₈ = 24.0 when T₈ = 0.88T₇ + 35.16

T₈ = 0.88(320.29) + 35.16

T₈ = 317.02 K

At t₉ = 27.0 when T₉ = 0.88T₈ + 35.16

T₉ = 0.88(317.02) + 35.16

T₉ = 314.14 K

At t₁₀ = 30 when T₁₀ = 0.88T₉ + 35.16

T₁₀ = 0.88(314.14) + 35.16

T₁₀ = 311.60 K

At t₁₁ = 33.0 when T₁₁ = 0.88T₁₀ + 35.16

T₁₁ = 0.88(311.60) + 35.16

T₁₁ = 309.37 K

At t₁₂ = 36.0  when T₁₂ = 0.88T₁₁ + 35.16

T₁₂ = 0.88(309.37)+ 35.16

T₁₂ = 307.41 K

At t₁₃ = 39.0  when T₁₃ = 0.88T₁₂ + 35.16

T₁₃ = 0.88( 307.41) + 35.16

T₁₃ = 305.68 K

At t₁₄ = 42.0  when T₁₄ = 0.88T₁₃ + 35.16

T₁₄ = 0.88(305.68) + 35.16

T₁₄ = 304.16 K

At t₁₅ = 45.0  when T₁₅ = 0.88T₁₄ + 35.16

T₁₅ = 0.88(304.16) + 35.16

T₁₅ = 302.82 K

At t₁₆ = 48.0  when T₁₆ = 0.88T₁₅ + 35.16

T₁₆ = 0.88(302.82) + 35.16

T₁₆ = 301.64 K

At t₁₇ = 51.0  when T₁₇ = 0.88T₁₆ + 35.16

T₁₇ = 0.88(301.64) + 35.16

T₁₇ = 300.60 K

At t₁₈ = 54.0  when T₁₈ = 0.88T₁₇ + 35.16

T₁₈ = 0.88(300.60) + 35.16

T₁₈ = 299.69 K

At t₁₉ = 57.0  when T₁₉ = 0.88T₁₈ + 35.16

T₁₉ = 0.88(299.69) + 35.16

T₁₉ = 298.89 K

At t₂₀ = 60  when T₂₀ = 0.88T₁₉ + 35.16

T₂₀ = 0.88(298.89) + 35.16

T₂₀ = 298.18 K

Answer:

Equilibrium

Explanation:

When forces in a system are in balance, there is equilibrium.

A balance of forces around a system causes equilibrium of a system.

Answer:

a. 0.32 b. 1448 m/s

Explanation:

We know v ∝ √T where v = velocity of sound and T = absolute temperature.

Let v₁ = velocity of sound at 17°, v₁ = fλ where f = frequency of sound = 512 Hz and λ = 66.5 cm = 0.665 m

So, v₁ = fλ = 512 Hz × 0.665 m = 340.48 m/s

T₁ = 17 + 273 = 290 K

Let v₂ = velocity of sound in air at NTP = unknown and T₂ = temperature at NTP = 0°C + 273 = 273 K

Now v₁/v₂ = √T₁/√T₂

So, v₂ = (√T₂/√T₁)v₁

= [√(T₂/T₁)]v₁

substituting the values of the variables, we have

v₂ =  [√(273 K/290 K)]340.48 m/s

v₂ =  [√0.9413]340.48 m/s

v₂ = (0.9702)340.48 m/s

v₂ = 330.35 m/s

Also v = √(γP/ρ) where v = velocity of sound in air at NTP  = 330.35 m/s, γ = ratio of molar heat capacities, P = pressure at NTP = 1.013 × 10⁵ Pa and ρ = density of air = 1.293 kg/m³

Since,  v = √(γP/ρ)

making γ subject of the formula, we have

γ = v²ρ/P

substituting the values of the variables, we have

γ = (330.35 m/s)² × 1.293 kg/m³/1.013 × 10⁵ Pa

= 31975.36 kg/m²s² ÷ 1.013 × 10⁵ Pa

= 0.32

b. Speed of sound in mercury v₃ = √(B/ρ) where B = Bulk modulus of mercury = 28.5 × 10⁹ Pa and ρ = density of mercury = 13600 kg/m³

v₃ = √(B/ρ)

= √(28.5 × 10⁹ Pa/13600 kg/m³)

= √(28.5 × 10⁹ Pa/13.6 × 10³ kg/m³)

= √(2.096 × 10⁶) m/s

= 1.448 × 10³ m/s

= 1448 m/s

Answer:

Have a great day!

Explanation:

Barometers. A barometer is a scientific instrument used to measure atmospheric pressure, also called barometric pressure.

Answer:

atmospheric  pressure

Explanation:

Answer:

[tex]7.3*10^{-7} \frac{N}{m^2}[/tex]

Explanation:

[tex]\frac{25}{(4*\pi*(0.095)^{2}*3*10^8 }[/tex]

Hope this is right and helps!

Answer:

a) Pabs = 345.7 [kPa]

b) F = 278.08 [N]

Explanation:

Manometric pressure in liquids is defined as the product of density by gravitational acceleration by the height of the liquid.

[tex]P_{g} =Ro*g*h[/tex]

where:

Pg = manometric pressure [Pa]

Ro = density = 0.890*10³[kg/m³]

g = gravity acceleration = 9.81 [m/s²]

h = liquid height = 28 [m]

Now the absolute pressure is defined as the sum of the atmospheric pressure plus the manometric pressure

a)

[tex]P_{abs}=P_{man}+P_{gau}\\P_{abs}= 101300 + (890*9.81*28)\\P_{abs} = 345765.2 [Pa] = 345.7 [kPa][/tex]

b) To determine the force at that point

The pressure is now defined as the relationship of a force over the area.

[tex]P=F/A\\F = P*A\\[/tex]

But the area of a circle can be calculated as follows:

[tex]A=\frac{\pi }{4} *(0.032)^{2}\\A = 0.0008042[m^{2}] \\F = 345765.2*0.0008042\\F = 278.08 [N][/tex]

Answer:

860 km

Explanation:

430*2=860

Answer:

c. You would weigh less on planet A because the distance between

you and the planet's center of gravity would be smaller.

Explanation:

The statement that best describes your weight on each planet is that you would weigh less on planet A because the distance between you and the planet's center of gravity would be smaller.

Since weight is dependent on the force of gravity and mass, the planet with more gravitational pull will have masses on them weighing more.

Answer:it’s D for ape x

Explanation:          

Answer:

225nm

Explanation:

The Maxima of diffraction girating

dsin( θ)= m(λ)

Where θ)= angle between central axis and corresponding point

The wavelength is to corresponding sin( θ)

Then the maximum number of (λ) can be seen by setting sin( θ)= 1 then

d= m(λ)

At fifth order maximum m=1 then

d= 5(λ)

Where d= distance between the slit and with girating of 1/890rullig/mm

d= 1/890rullig/mm= 8.90×10^-6m

At maximum wavelength

d= 5(λ)

(λ)=5/d

= 8.90×10^-6m/5

=2.75*10^-7

= 275nm

Therefore, longest wavelength that forms an intensity maximum in the fifth order is 275nm