6. At the moment when a bodybuilder throws a 10.0kg medicine ball, it is exactly 2.0m above the ground and traveling at 5.0 m/s. It reaches a maximum height of 3.0m above the ground and then falls to the ground. Assume that air resistance is negligible. a. What is the potential energy of the ball as it leaves the hands relative to the ground? b. What is the kinetic energy of the ball as it leaves the hands? c. What is the total mechanical energy (kinetic plus potential) of the ball as it left the hands? 1.200 d. What is the total mechanical energy of the shot JUST as it reaches its maximum height? e. What is the potential energy of the shot just as it reaches its maximum height? f. What is the kinetic energy of the shot just as it reaches its maximum height?

A 500 kg cart rests atop a hill 30.0 m high on a roller coaster. Its gravitational potential energy is measured relative to the bottom of the hill. The cart then rolls down the hill. Which of these best describes what is happening in this situation?   a. the total mechanical energy of the cart is decreasing, the kinetic energy of the cart is increasing, and the gravitational potential energy of the cart is increasing   b. the total mechanical energy of the cart is increasing, the kinetic energy of the cart is increasing, and the gravitational potential energy of the cart is increasing   c. the total mechanical energy of the cart is increasing, the kinetic energy of the cart is increasing, and the gravitational potential energy of the cart is decreasing   d. the total mechanical energy of the cart is increasing, the kinetic energy of the cart is decreasing, and the gravitational potential energy of the cart is increasing   e. the total mechanical energy of…

X Problem 1. An NFL punter punts a 0.02 kg football 100 meters into the air. A. What is the initial potential energy of the ball when it's at its peak? 0.02 x 9.8 x 100 = 19.6 j What is its final kinetic energy before it hits the ground? 1 o add speaker notes B. C. What is the velocity of the ball before it hits the ground? در نگاه U EVA

2. A 3.2 kg ball that is moving straight upward has 17 J of kinetic energy and its total mechanical energy is 25 1. a. Find the gravitational potential energy of the ball. b. What is its height above the ground? c. What is the speed of the ball? d. What will be its gravitational energy when it is at Its highest point above the ground? e. What is the maximum height above the ground? f. What will be its speed Just before it lands on the ground? and Given: quired: ution:

4. A 4.21-kg watermelon is released from rest from the roof of an 27.8-m-tall building. a. Calculate the work done by gravity on the watermelon as it falls from the roof to the ground. b. Calculate the net work done on the watermelon as it falls to the ground. Show clearly how you get your answer. Just before it hits the ground, what is the watermelon's kinetic energy? Show clearly how you get your answer. d. Just before it hits the ground, what is the watermelon's speed? (Use energy techniques to answer this.) C.

A freight elevator weighs 6200 N. What is the power required to raise the elevator a. What a distance of 20 meters in 10 seconds? b. One of the motors for the freight elevator system goes out. Now the maximum power available to move the 6200 N freight elevator is 10 kW. How long does it take to raise the elevator 20 meters now?

I need help with 2a and 2b

A car is accelerated from velocity v1 to v2 in the time period of t . The mass of the car is m. The inclined angle of the hill is α. The distance travelled along the hill is L. The vertical distance travelled is H. Select the equation used to calculate the potential energy increase of the car ΔPE______     A.     B. ΔPE=mgH   C. ΔPE=mgL   D.

You throw a basketball straight up into the air with an initial velocity of 5.6 m/s. The ball leaves your hand 1.2 meters above the ground. It moves upwards, stops, and then goes all the way down until it hits the ground (below the height you threw from).A. Use conservation of energy (and not the kinematics equations) to calculate the velocity of the ball the instant before it hits the ground.

A. Ignoring air drag, what is the takeoff speed of such a flea? (in m/s) B. Calculate the kinetic energy of this flea at takeoff (in J) C. Calculate the kinetic energy per kilogram of mass (in J/kg) D. If a 73.0 kg, 1.80 m tall human could jump to the same height compared with his length as the flea jumps compared with its length, how high could the human jump? (in m) E. If a 73.0 kg, 1.80 m tall human could jump to the same height compared with his length as the flea jumps compared with its length, what takeoff speed would the man need? (in m/s) F. Most humans can jump no more than 60.0 cm from a crouched start. What is the kinetic energy per kilogram of mass at takeoff for such a 73.0 kg person? (in J/kg)