500 J of work are done in 4 seconds to lift a 40 kg box to the top of a high shelf. How much power was required to complete the lift?

Why does it take less time for small rocks to wear away than it does for large rocks to wear way?

In being served, a tennis ball is accelerated from rest to a speed of m/s. the average power generated during the serve is 2920 w. assuming that the acceleration of the ball is constant during the serve, find the force acting on the ball.

A dolphin is trying to jump through a hoop that is fixed at a height of 3.5 m above the surface of her pool. The dolphin leaves the water at an angle of inclination of 40°.

Does an object need a force to start moving

To recharge a 12 v battery, a battery charger must move 3.3 * 105 c of charge from the negative terminal to the positive terminal. how much work is done by the battery charger? answer in units of j

A 21.6-kg cube made from aluminum is at its melting temperature of 660℃. If you were to add 8000 kJ worth of energy as heat, what percent of the block melts? You might need the following: α = 23.0 ✕ 10-6 K-1, β = 69.

What are all of types of radiation the sun produces?

Can all waves be distorted, deflected, or changed? Explain your response.

Compare the momentum of a 6,300-kg elephant walking 0.11 m/s and a 50-kg dolphin swimming 10.4 m/s. your answer

What happens when the thermal energy of a substance increases? A. The motion of the particles in the substance increases, and the temperature of the substance decreases. B.