Timmy is sat down in class, looking around the room. He notices a water bottle on a desk next to him and thinks to himself that since the water bottle is on the desk it must not have kinetic energy. Is he right yes, or no? Explain?

A 68.5-kg athlete leaps straight up into the air from a trampoline with an initial speed of 8.7 m/s. The goal of this problem is to find the maximum height she attains and her speed at half maximum height. (a) What are the interacting objects and how do they interact? (b) Select the height at which the athlete's speed is 8.7 m/s as y = 0. What is her kinetic energy at this point? What is the gravitational potential energy associated with the athlete? (c) What is her kinetic energy at maximum height? What is the gravitational potential energy associated with the athlete? (d) Write a general equation for energy conservation in this case and solve for the maximum height. Substitute and obtain a numerical answer. m (e) Write the general equation for energy conservation and solve for the velocity at half the maximum height. Substitute and obtain a numerical answer. m/s

Jane and Jake are looking at what happens to body 1 of mass m and body 2 of mass 2m, initially at rest, when equal forces are applied separately to the two bodies. Jake says that equal forces applied for equal times do equal amounts of work on the two bodies. Jane says that the two forces do equal amounts of work only if the two bodies move equal distances in the direction of the forces. Which one, if either, is correct? O Jake, because the speed of body 1 is half the speed of body 2, but m¡v1= m2V2- O Jane, because work does not depend on mass, only on force times distance. O Jake, because all bodies travel equal distances when equal forces are applied for equal times. O Jane, because it takes the same time for all bodies to travel equal distances when equal forces are involved. O Neither, because we can't compare the amounts of work done on bodies of different mass.

A coffee filter of mass 1.5 grams dropped from a height of 1 m reaches the ground with a speed of 0.7 m/s. How much kinetic energy Kair did the air molecules gain from the falling coffee filter? Start from the Energy Principle, and choose as the system the coffee filter, the Earth, and the air. J

Speed Car A 58 MPH Car B 64 MPH Car C 60 MPH Car D 63 MPH Cars A, B, C, and D are traveling at different speeds in four different lanes on the highway. Evaluate the data and select the list ordering cars with the MOST energy to the LEAST energy?

A diver of mass 68 kg stands on a diving board 5.0 m above a pool. At the moment of the jump, the diving board transfers its 3400 J of energy to the diver, who leaves the board at an angle of 35°. a. What is the speed of the diver just before they enter the water? b. Suppose that when the diver enters the water, they experience an acceleration of a->water= +4 m/ss J. What is the minimum depth of the pool necessary so that this diver comes to rest exactly at the bottom of the pool

A 79 kg bike racer climbs a 1100m long section of road that has a slope of 4.3∘.  By how much does his gravitational potential energy change during this climb? Express your answer with the appropriate units

You are meeting your friends at a 49er football game. You start near the top of the seating area (8.9 m above the field) and walk down the steps to where your friends are sitting (3.4 m above the field). Assume that your mass is 60 kg. What is the change in your gravitational potential energy as you walk down the steps? Give your answer in J and report your answer to 1 decimal place. Make sure you include the sign if that is important for your answer.

Let's now work through an example using conservation of energy. Let's say a small, rubber ball with a mass of 1.00 kg is launched straight up in the air from ground level by a toy compressed-air cannon. Assume that the cannon is small, so we'll consider the initial height of the ball to be zero when it leaves the cannon. The initial speed of the ball when leaves the cannon is 11.5 m/s. Our goal is to find the maximum height the ball reaches before it begins to fall. You may have solved similar type of problem when studying kinematics. But now, let's apply conservation of energy to this problem. If we assume, reasonably, that air resistance is minimal, then our ball-Earth system a closed system. That means the total energy of the system is constant, or E₁ = E₁, the final total energy is equal to the initial total energy. Since the initial potential energy and final kinetic energy are zero, our equation now becomes Epf = Eki We can then substitute the formula for kinetic energy, Ex=mv²,…

The work required by Neymar to push a box of soccer balls on a horizontal, frictionless floor to accelerate it from a speed of zero to v is W1. The work required by Neymar to accelerate the box of soccer balls on the same floor, from v to 2v is W2. The ratio of W2 to W1 is   The correct answer is 3 but I don't know how they got to that answer