A ball toy of mass 22.7 g is thrown straight up with an initial speed of 2.8 m/s. Neglect air resistance. If the gravitational potential energy is taken to be zero at the maximum height the toy reaches, what uld the gravitational potential energy be in J when it leaves the hand? Give the answer to 2 decimal places

A roller coaster with a mass of 725 kg starts with a speed of 22.0 m/s at the bottom of a hill.  At the top of the hill the roller coaster has a speed 14.0 m/s.(see diagram below). Assuming friction is minimal, what is the height of the hill? ? Give your answer in m to 2 decimal places.

A roller coaster starts with a speed of 4.1 m/s at a point 51 m above the bottom of a dip. Neglecting friction, what wil be the speed of the roller coaster at the top of the next slope, which is 30 m above the bottom of the dip? Answer: m/s

A weight lifter bench‑presses a 150.0 kg barbell from his chest to a height equal the length of his arms, 0.850 m. How much work does he do? How many food calories does the weight lifter use if he does this lift 35 times? Assume the weight lifter does no work in letting the barbell drop back to his chest.

Given: A tennis ball of mass m = 0.063 kg is thrown straight up with an initial speed v0 = 7 m/s. Let the gravitational potential energy be zero at the initial height of the tennis ball. What is the maximum height, h in meters, the ball reaches?  What is the work done by gravity, Wg in Joules, during the ball's flight to its maximum height?

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How much potential energy does a person of mass 82kg have if they are standing at the top of a building that is 59.6 m high? sumbit your answer is exponential form.

A center throws a basketball m = 1 kg straight up with an initial speed of vo = 9.5 m's. He releases the ball at shoulder | height ho = 1.9 m. Let gravitational potential energy be zero at ground level. Give the total mechanical energy of the ball E in terms of maximum height h it reaches, the mass m, and the gravitational acceleration g. E= What is the height, hm in meters? 9 HOME

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You are driving to work at 60 mph and need to accelerate to 75 mph. How long will it take to reach this speed? Express this quantity in units of seconds. Assume the engine is rated at 140 hp and is 25% efficient. The combined vehicle and driver mass is 2970 lbm.