What is energy?  Explain why scientists care about this concept as part of their work.

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a. Gravitational potential energy and mechanical energy Ob. Potential energy and mechanical energy c. Gravitational potential energy and kinetic energy Od. Potential energy and kinetic energy Clear my choice When a stone is dropped from a bridge to a river below, what happens to the gravitational potential energy halfway down? f 2 Select one: O a. The stone has half the amount of gravitational potential energy and double the amount of kinetic energy. O b. The stone has half the amount of gravitational potential energy and half of it has been converted to kinetic energy. O C. The stone gains momentum, and its potential energy decreases and its kinetic energy increases. O d. The stone gains momentum, and its potential energy decreases. Jamie pulls an elastic band that has a spring constant of 45 N/m, producing a 3.0 J increase in potential energy. How far did Jamie hp

1. Refer to figure 1. The 10.0 kg green cart travels down a ramp - from point A to B. Calculate its starting potential energy, kinetic energy at the bottom of the ramp, and its velocity coming off the bottom of the ramp. If the cart coasts from points B to C, did it do any work? How far up the 2nd ramp does the cart go as measured from the ground? 10.0m Figure 1 B

A 1000 kg car traveling at 40 m/s slows to 15 m/s. What is the initial kinetic energy of the car? What is the final kinetic energy of the car? How much work is done on the car in slowing it down? What force does the work on the car?  As solved when asked in a different question, I know that the initial kinetic energy is 800,000 J, the final kinetic energy is 112,500 J, and the work is -687500 J. How ever i still need the force.

What is absolute zero?     What is kinetic energy and potential energy? Give examples.     You have a ball in your hand above the ground at rest which you then drop.  What energy is involved in each part of this situation and how do we know that total mechanical energy has been conserved?  Explain with and without air resistance present.   A boulder and a pebble are sitting on a cliff, which has greater gravitational potential energy and why? A cheetah and a person are racing, both has the same mass, which has a greater kinetic energy and why? What is temperature? How does an objects temperature relate to motion of the molecules?     What is heat?     Describe thermal expansion/contraction. When temperature rises, which one occurs?   I have a 2kg ball on a cliff 10m high. If the gravitational acceleration on this planet is 4m/s2, what is the GPE of the ball?     A 2kg ball is rolled at 3m/s. What is the KE of the ball?   What is work? And what are the units for work? How does this…

1. A roller-coaster car with a mass of 1200 kg starts at rest from a point 20 m above the ground. At point B, it is 9 m above the ground. [Express your answers in kilojoules (kJ).] a. What is the initial potential energy of the car? b. What is the potential energy at point B? c. If the initial kinetic energy was zero and the work done against friction between the starting point and point B is 40 000 J (40 kJ), what is the kinetic energy of the car at point B 2. The time required for one complete cycle of a mass oscillating at the end of a spring is 0.80 s. What is the frequency of oscillation?

The figure below shows a graph of v, versus t for the motion of a motorcyclist as he starts from rest and moves along the road in a straight line. v. (m/s) 10 8. 6 2 t (s) 12 4. 8 10 (a) Find the average acceleration for the time interval t = 0 to t = 12.0 s. 0.3 V m/s2 (b) Estimate the time at which the acceleration has its greatest positive value. 3 What is the value of the acceleration at that instant? 0.2 Your response is off by a multiple of ten. m/s2 (c) When is the acceleration zero? Acceleration is zero whent = 0 The correct answer is not zero. s and when t > 0 The correct answer is not zero. s.

Please solve and answer the question correctly. Thank you!