Answer:
Power_input = 85.71 [W]
Explanation:
To be able to solve this problem we must first find the work done. Work is defined as the product of force by distance.
[tex]W = F*d[/tex]
where:
W = work [J] (units of Joules)
F = force [N] (units of Newton)
d = distance [m]
We need to bear in mind that the force can be calculated by multiplying the mass by the gravity acceleration.
Now replacing:
[tex]W = (80*10)*3\\W = 2400 [J][/tex]
Power is defined as the work done over a certain time. In this way by means of the following formula, we can calculate the required power.
[tex]P=\frac{W}{t}[/tex]
where:
P = power [W] (units of watts)
W = work [J]
t = time = 40 [s]
[tex]P = 2400/40\\P = 60 [W][/tex]
The calculated power is the required power. Now as we have the efficiency of the machine, we can calculate the power that is introduced, to be able to do that work.
[tex]Effic=0.7\\Effic=P_{required}/P_{introduced}\\P_{introduced}=60/0.7\\P_{introduced}=85.71[W][/tex]
Look at this model of an atom. Where are the electrons located and how many are there?
Answer:
The electrons are on the outer shell, there are 10 of them.
Explanation:
There are two in the inner shell and eight in the outer shell, giving us a total of 10 electrons
A little girl is walking, swinging her arms through a 20° angle every 0.25 s. The length of each arm is 30 cm. Assuming that the arms move with constant speed during each swing, find the force that the blood vessel in her arm would exert on a 1-gram drop of blood from the end of the arm if her arm were not swinging.
Answer:
The force will be "[tex]9.8\times 10^{-3} \ N[/tex]".
Explanation:
The given values are:
Mass,
m = 1 gram
Angle,
Ф = 20°
As we know,
⇒ [tex]F=mg[/tex]
On substituting the given values in the above expression, we get
⇒ [tex]=(1.0\times 10^{-3})(9.8)[/tex]
⇒ [tex]=9.8\times 10^{-3} \ N[/tex]
a steel girder weighting 700 lb is hoisted from gund level to the roof of a 70-ft building using a chain that weighs 4lb/running foot. Find the work done
Answer:
66.475kJ
Explanation:
Work done is the product of the force and perpendicular distance in direction of the force.
Work done = Force × distance
Given
Weight = 700lb
Distance = 70ft
1lb force = 4.448N
700lb force = 700(4.448) = 3113.6N
Distance = 70(0.305) = 21.35m
Work done = 3113.6×21.35
Work done ≈ 66,475Joules
Work done = 66.475kJ
g During the contraction of the heart, 65 cm3 blood is ejected from the left ventricle into the aorta with a velocity of approximately 98 cm/s. The blood volume traverses the aortic arch, exiting with the same speed but opposite direction. Assume the mass density of the blood is 1060 kg/m3 blood, the aortic arch remains stationary, and that the heart rate is 61 bpm. What is the average force exerted by the blood on the wall of the aorta.
Answer:
The force is [tex]F = 0.1441 \ N[/tex]
Explanation:
From the question we are told that
The volume of blood ejected is [tex]V_b = 65cm^3 = 65*10^{-6} \ m^3[/tex]
The velocity of the ejected blood is [tex]v = 98 cm/ s = 0.98 \ m/s[/tex]
The mass density of blood is [tex]\rho = 1060 \ kg/m^3[/tex]
The heart rate is [tex]R = 61 bpm(beats \ per \ miunite) = \frac{61}{60} = 1.0667\ bps[/tex]
Generally the average force exerted is mathematically represented as
[tex]F = 2 * \rho * V_b * R * v[/tex]
=> [tex]F = 2 * 1060 * (65*10^{-6}) *1.0667 * 0.98[/tex]
=> [tex]F = 0.1441 \ N[/tex]
Assume that, when we walk, in addition to a fluctuating vertical force, we exert a periodic lateral force of amplitude 25 NN at a frequency of about 1 HzHz. Given that the mass of the bridge is about 2000 kgkg per linear meter, how many people were walking along the 144-mm-long central span of the bridge at one time, when an oscillation amplitude of 75 mmmm was observed in that section of the bridge
Complete Question
The complete question is shown on the first uploaded image
Answer:
Explanation:
From the question we are told
The amplitude of the lateral force is [tex]F = 25 \ N[/tex]
The frequency is [tex]f = 1 \ Hz[/tex]
The mass of the bridge per unit length is [tex]\mu = 2000 \ kg /m[/tex]
The length of the central span is [tex]d = 144 m[/tex]
The oscillation amplitude of the section considered at the time considered is [tex]A = 75 \ mm = 0.075 \ m[/tex]
The time taken for the undriven oscillation to decay to [tex]\frac{1}{e}[/tex] of its original value is t = 6T
Generally the mass of the section considered is mathematically represented as
[tex]m = \mu * d[/tex]
=> [tex]m = 2000 * 144[/tex]
=> [tex]m = 288000 \ kg[/tex]
Generally the oscillation amplitude of the section after a time period t is mathematically represented as
[tex]A(t) = A_o e^{-\frac{bt}{2m} }[/tex]
Here b is the damping constant and the [tex]A_o[/tex] is the amplitude of the section when it was undriven
So from the question
[tex]\frac{A_o}{e} = A_o e^{-\frac{b6T}{2m} }[/tex]
=> [tex]\frac{1}{e} =e^{-\frac{b6T}{2m} }[/tex]
=> [tex]e^{-1} =e^{-\frac{b6T}{2m} }[/tex]
=> [tex]-\frac{3T b}{m} = -1[/tex]
=> [tex]b = \frac{m}{3T}[/tex]
Generally the amplitude of the section considered is mathematically represented as
[tex]A = \frac{n * F }{ b * 2 \pi }[/tex]
=> [tex]A = \frac{n * F }{ \frac{m}{3T} * 2 \pi }[/tex]
=> [tex]n = A * \frac{m}{3} * \frac{2\pi}{25}[/tex]
=> [tex]n = 0.075 * \frac{288000}{3} * \frac{2* 3.142 }{25}[/tex]
=> [tex]n = 1810 \ people[/tex]
If a sinusoidal electromagnetic wave with intensity 18 W/m2 has an electric field of amplitude E, then a 36 W/m2 wave of the same wavelength will have an electric field of amplitude?
a. 4E
b. 2 underroot 2E
c. 2E
d. underroot E
Answer:
The correct option is D
Explanation:
From the question we are told that
The intensity of the first electromagnetic wave is [tex]I = 18 \ W/m^2[/tex]
The amplitude of the electric field is [tex]E_{max}_1 =A[/tex]
The intensity of the second electromagnetic wave is [tex]I = 36 \ W/m^2[/tex]
Generally the an electromagnetic wave intensity is mathematically represented as
[tex]I = \frac{1}{2} * \epsilon_o * c * E_{max}^2[/tex]
Looking at this equation we see that
[tex]I \ \ \alpha \ \ E^2_{max}[/tex]
=> [tex]\frac{I_1}{I_2} = [ \frac{ E_{max}_1}{ E_{max}_2} ] ^2[/tex]
=> [tex]E_{max}_2 = \sqrt{\frac{x}{y} } * E_{max}_1[/tex]
=> [tex]E_{max}_2 = \sqrt{\frac{36}{18} } * E[/tex]
=> [tex]E_{max}_2 = \sqrt{2 } E[/tex]
two asteroids crashed the crash caused both asteroids to change speeds scientist want to use the change
Answer:
The force each one experienced
Explanation:
Hope this helps :)
What effect does atmospheric pressure have on density?
Answer:sometimes it commits to how it will happen
Explanation:
Answer:
Atmospheric pressure increases density
Explanation:
Atmospheric pressure decreases the volume of space, since volume is inversely proportional to density, density will increase.
Which of the following is true for valence electrons?
Valence electrons are always located in the outer most energy level.
Valence electrons are found only in radioactive isotopes.
Valence electrons are always located in the innermost energy level
Valence electrons are found only in negatively charged ions.
Answer:
Valence electrons are always located in the outer most energy level.
Explanation:
Valence electrons are the ones that are involved in chemical bonds. In order to take part in a chemical bonding, the outermost/valence electron needs to be involved. Thus, the answer is Valence electrons are always located in the outer most energy level.
Suppose three forces are acting on a model rocket launching into the air. The force of gravity is 1.2 N acting downward. The rocket engine has a force of 12.3 N acting at an angle of 65⁰ above the horizontal to the right. The wind pushes the rocket with a force of 2.5 N to the left. Find the magnitude and direction of the resultant force on the rocket.
Please answer!!! Offering 50 points for answer and explanation
Answer:
can you include a picture
Decompose the forces acting on the rocket in horizontal and vertical components.
• net horizontal force:
∑ F = (12.3 N) cos(65°) - 2.5 N ≈ 2.7 N
(notice we're taking "to the right" to be the positive direction)
• net vertical force:
∑ F = (12.3 N) sin(65°) - 1.2 N ≈ 9.9 N
The resultant force then has magnitude
√((2.7 N)² + (9.9 N)²) ≈ 10.3 N
Since the horizontal and vertical components of the resultant are both positive, it points at an angle between 0° and 90° from the positive horizontal, so that
tan(θ) ≈ (9.9 N) / (2.7 N) ≈ 3.69
===> θ ≈ arctan(3.69) ≈ 75°
HELP ASAP!! i’ll mark you the brainliest!!
Answer:
yes
Explanation:
The two images show side views of ocean waves. How are the two sets of waves different?
Mark all the units for speed
Answer:
Speed. I am speed.
Explanation:
The FitnessGram Pacer Test is a multistage aerobic capacity test that progressively gets more difficult as it continues. The 20 meter pacer test will begin in 30 seconds. Line up at the start. The running speed starts slowly, but gets faster each minute after you hear this signal. A single lap should be completed each time you hear this sound. Remember to run in a straight line, and run as long as possible.
Use the following information to answer questions 4 and 5:
A rock is launched vertically into the air at a velocity of 14.75 m/s.
4. Toby claims that the rock must come to rest before it can fall back towards the ground. Is Toby
correct?
A. Toby is correct because the rock is experiencing a negative acceleration, causing its negative
velocity to increase until the rock reaches a velocity of O m/s before becoming positive.
B. Toby is correct because the rock is experiencing a negative acceleration, causing its positive
velocity to decrease until the rock reaches a velocity of O m/s before becoming negative.
C. Toby is incorrect because the rock is experiencing a positive acceleration, causing its positive
velocity to increase in magnitude.
D. Toby is incorrect because the rock is experiencing a negative acceleration, causing its positive
velocity to increase in magnitude.
5. Calculate the time it takes for the rock to reach its maximum height.
A. 1.50 seconds
B. 2.47 seconds
C. 3.00 seconds
D. 4.94 seconds
Question 4
B. Toby is correct because the rock is experiencing a negative acceleration, causing its positive velocity to decrease until the rock reaches a velocity of O m/s before becoming negative.
Question 5
At the maximum height, velocity is 0, so:
v = v₀ - gt
0 = 14.75 - 9.8t
t = 14.75/9.8
t = 1.5 s (OPTION A)
4). In the given situation, the assertion that could be made regarding Toby would be:
B). Toby is correct because the rock is experiencing a negative acceleration, causing its positive velocity to decrease until the rock reaches a velocity of O m/s before becoming negative.
5). The time that would be taken by the rock to attain its greatest height would be:
1.5 second
4). Tobby correctly states as rock would be undergoing a -ve acceleration which leads its +ve velocity to fall by the time rock attains the velocity of 0 m/s.
Thus, option B is the correct answer.
5). Given that,
Initial velocity([tex]v_{0}[/tex]) = 14.75 m/s
As we know,
Velocity remains 0 m/s at the greatest height,
So,
Velocity(v) [tex]= v_{0} - gt[/tex]
where
[tex]0 = 14.75 - 9.8t[/tex]
⇒ [tex]t = 14.75/9.8[/tex]
∵ [tex]t = 1.5 s[/tex]
Learn more about "Velocity" here:
brainly.com/question/18084516
Numerical Problems
A bus covers a distance of 600 metres in 30 seconds. Calculate the speed of
the bus.
Answer:
20 m/s.
Explanation:
From the question given above, the following data were obtained:
Distance travelled = 600 m
Time taken = 30 s
Speed =?
Speed can be defined as the distance travelled per unit time. Mathematically, it is expressed as:
Speed = Distance /time
With the above formula, we can easily calculate the speed of the bus as follow:
Distance travelled = 600 m
Time taken = 30 s
Speed =?
Speed = Distance /time
Speed = 600 / 30
Speed = 20 m/s
Therefore, the speed of the bus is 20 m/s.
CUP 6. A wire has a diameter of 0.032 inches. The AWG rating of this wire is most likely to be O A. 20 O B. 14. O C. 12. O D. 18.
Answer:
A. 20
Explanation:
The AWG rating of the wire can be determined by applying the formula;
[tex]d_{i}[/tex] = 0.005 x [tex]92^{\frac{(36 - s)}{39}} }[/tex]
where [tex]d_{i}[/tex] is the diameter of wire in inches, and s is the diameter of wire in AWG.
Given that [tex]d_{i}[/tex] = 0.032 inches, then;
0.032 = 0.005 x [tex]92^{\frac{(36 - s)}{39}} }[/tex]
[tex]\frac{0.032}{0.005}[/tex] = [tex]92^{\frac{(36 - s)}{39}} }[/tex]
6.4 = [tex]92^{\frac{(36 - s)}{39}} }[/tex]
Find the log of both sides to have,
log 6.4 = log [tex]92^{\frac{(36 - s)}{39}} }[/tex]
log 6.4 = [tex](\frac{36 -s}{39})[/tex] log 92
[tex]\frac{log 6.4}{log92}[/tex] = [tex](\frac{36 -s}{39})[/tex]
0.410523 = [tex](\frac{36 -s}{39})[/tex]
36 - s = 0.410523 x 39
= 16.0104
⇒ s = 36 - 16.0104
= 19.9896
s = 20
Therefore, the AWG of the wire is 20.
giving brainiest to correct answer.
Imagine a 0.2 kg ball moving at 5 m/s colliding with a 0.3 kg ball moving at 2 m/s in the same direction. After the collision the 0.2 kg green ball stops moving and the 0.3 kg purple ball continues moving in the same direction.
giving brainiest to correct answer.
Answer:
[tex]5.33\ m/s[/tex]
Explanation:
[tex]We\ know\ that,\\Momentum=Mass*Velocity\\p=mv\\Hence,\\Lets\ first\ consider\ the\ case\ of\ the\ two\ balls\ 'Before\ Collision':\\\\Mass\ of\ the\ green\ ball=0.2\ kg\\Initial\ Velocity\ of\ the\ green\ ball=5\ m/s\\Initial\ Momentum\ of\ the\ green\ ball=5*0.2=1\ kg\ m/s\\\\Mass\ of\ the\ pink\ ball=0.3\ kg\\Initial\ Velocity\ of\ the\ pink\ ball=2\ m/s\\Initial\ Momentum\ of\ the\ pink\ ball=0.3*2=0.6\ kg\ m/s\\\\Total\ momentum\ of\ both\ the\ balls\ 'Before\ Collision'=1+0.6=1.6\ kg\ m/s[/tex]
[tex]Hence,\\Lets\ now\ consider\ the\ case\ of\ the\ two\ balls\ 'After\ Collision':\\\\Mass\ of\ the\ green\ ball=0.2\ kg\\Final\ Velocity\ of\ the\ green\ ball=0\ m/s\\Final\ Momentum\ of\ the\ green\ ball=0\ kg\ m/s\\\\Mass\ of\ the\ pink\ ball=0.3\ kg\\Final\ Velocity\ of\ the\ pink\ ball=v\ m/s\\Final\ Momentum\ of\ the\ pink\ ball=0.3*v=0.3v\ kg\ m/s\\\\Total\ momentum\ of\ both\ the\ balls\ 'After\ Collision'=0+0.3v=0.3v\ kg\ m/s[/tex]
[tex]As\ we\ know\ that,\\Through\ the\ law\ of\ conservation\ of\ momentum,\\In\ an\ isolated\ system:\\Total\ Momentum\ Before\ Collision=Total\ Momentum\ After\ Collision\\Hence,\\1.6=0.3v\\v=\frac{1.6}{0.3}=5.33\ m/s[/tex]
What is food called when it enters the pharynx?
A.Bile
B.bolus
C. Food
D. Feces
Answer:
its food this was easy
Which statement accurately describes thermal energy?
Answer:
here are the options.
Answer:
the energy that is associated with temperature or D
Explanation:
Hope this helps
A solid ball is rolling along a horizontal surface at 3.7 m/s when it encounters an upward
incline. If it rolls without slipping up the incline, what maximum height will it reach?
Answer:
h = 0.697 [m]
Explanation:
To solve this problem we must use the energy conservation theorem, where it tells us that kinetic energy is converted to potential energy or vice versa.
[tex]E_{kinet}=E_{pot}[/tex]
where:
Ekinet = kinetic energy [J]
Epot = potential energy [J]
[tex]\frac{1}{2}*m*v^{2}=m*g*h\\0.5*(3.7)^{2} =9.81*h\\h =(6.845)/9.81\\h = 0.697 [m][/tex]
in which part of the circulatory system can the exchange of gases and nutrients take place?
an unladen swallow flies 5 m/s how far has the bird traveled after 1 minute?
Answer: 300m
1 minute = 60s
the unladen swallow can fly: 60.5 = 300 (m)
Explanation:
A satellite orbits the Earth (mass = 5.98 x 1024 kg) once every = 43200 s. At what radius does the satellite orbit?
Answer:
26621 km
Explanation:
We are given;
Mass: m = 5.98 x 10^(24) kg
Period; T = 43200 s
Formula for The velocity(v) of the satellite is:
v = 2πR/T
Where R is the radius
Formula for centripetal acceleration is;
a_c = v²/R
Thus; a_c = (2πR/T)²/R = 4π²R/T²
Formula for gravitational acceleration is:
a_g = Gm/R²
Where G is gravitational constant = 6.674 × 10^(-11) m³/kg.s²
Now the centripetal acceleration of the satellite is caused by its gravitational acceleration. Thus;
Centripetal acceleration = gravitational acceleration.
Thus;
4π²R/T² = Gm/R²
Making R the subject gives;
R = ∛(GmT²/4π²)
Plugging in the relevant values;
R = ∛((6.674 × 10^(-11) × 5.98 x 10^(24) × 43200²)/(4 × π²))
R = 26.621 × 10^(6) m
Converting to km, we have;
R = 26621 km
Answer:
2.66 *10^7
Explanation:
Sorry I don't know the process if you were interested in that :/
Just do the attachment
Answer: your answer is B I know that's what you picked but I believe it is correct! look below...
Explanation: A solution is made when one substance called the solute "dissolves" into another substance called the solvent. Dissolving is when the solute breaks up from a larger crystal of molecules into much smaller groups or individual molecules.
In order to form a solution, the solute must be surrounded, or solvated, by the solvent. Solutes successfully dissolve into solvents when solute-solvent bonds are stronger than either solute-solute bonds or solvent-solvent bonds.
BRAINLIEST?
An object whose specific gravity is 0.850 is placed in water. What fraction of the object is below the surface of the water?
Answer:
The fraction of the object that is below the surface of the water is ¹⁷/₂₀
Explanation:
Given;
specific gravity of the object, γ = 0.850
Specific gravity is given as;
[tex]specific \ gravity = \frac{density \ of the \ object}{density \ of \ water}\\\\0.85= \frac{density \ of the \ object}{1000 \ kg/m^3} \\\\density \ of the \ object = 850 \ kg/m^3[/tex]
Fraction of the object's weight below the surface of water is calculated as;
[tex]= \frac{850}{1000} \ \times\ 100\%\\\\= 85 \% \\\\= \frac{17}{20}[/tex]
Therefore, the fraction of the object that is below the surface of the water is ¹⁷/₂₀
A block that slides on a rough surface slows down and eventually stops. The reverse process never occurs. That is, a block at rest never begins to move and accelerate on a rough surface without the action of an external agent. The second situation is forbidden because it would violate:_________.
a) conservation of total energy
b) conservation of momentum
c) the first law of thermodynamics
d) the second law of thermodynamics
e) both the first and second law of thermodynamics
Gracias.
Answer:
d) the second law of thermodynamics
Explanation:
Here we take an example
The entropy represents a measurement of the energy dispersal in the system. Also, the campfire would an entropy example. The burning of the solid wood and then it became the ash, smoke and gases this all would be spread the energy to the outward as compared to the solid fuel
Therefore as per the given statement, the correct option is d.
In the formulas for latent heat of fusion and latent heat of vaporization, what does Q represent?
Answer:
Q is the amount of energy released or absorbed during the change of phase of the substance (in kJ or in BTU), m is the mass of the substance (in kg or in lb), and. L is the specific latent heat for a particular substance (kJ kg−1 or in BTU lb−1), either Lf for fusion, or Lv for vaporization.
I hope this helps∪ω∪
Answer:
A
Explanation:
Helppppp meeee plssss ASAP
Suppose the atoms of two different nonmetal elements bonded. What type of
substance would most likely form?
A. A metalloid
B. An ionic compound
C. A covalent compound
D. A third element
Answer:
C
Explanation:
covalent. Hope that helps!
If two ___ forces are applied to an object in opposite directions, the object does not move, or moves at a ___ , this means the forces are ___. If to ___ forces are applied to an object in opposite directions, the object does move, this means the forces are ___.
Answer:
Equal and opposite
Constant speed
Balanced
Unequal and non-opposite
Unbalanced
Explanation:
Balanced forces can be defined as forces which are equal in size but opposite in direction.
Now, these forces do not cause a change in motion because when they act on an object at rest, such an object will not move. For example, when attempt to push against a wall, the wall will push back with an equal but opposite force and neither you nor the wall will move.
While unbalanced forces are those that cause a change in the motion of an object.
Thus, these forces are said not to be equal and opposite.
A person pushing a bin with 45 N of force slides the 3 kg plastic bin on a rough surface with friction. The plastic bin is moving with a constant velocity. What is the net force acting on the box?
Answer:
F = 0
Explanation:
Given that,
Force acting to push a bin = 45 N
Mass of the plastic bin, m = 3 kg
The plastic bin is moving with a constant velocity.
We need to find the net force acting on the box. Constant velocity means the change in velocity is equal to 0. It means acceleration will be 0.
As a result, the force acting on the box is equal to 0.