Why are all machines not 100% efficient

A. Mass

B. Gravity

C. Friction

D. Distance

2. As the ball in the air falls back into the boy's hand, the speed of the ball A. goes up and then goes down B. stays the same C. decreases D. increases

If a photon has a frequency of 5.20 x 10^14 hertz, what is the energy of the photon? Given : Planck's constant is 6.63 x 10^-34 joule-seconds.

How can your personal listening style impact your communication?

At what age can a person begin taking actions that will reduce the risk of dementia

A force of 1 newton will cause a mass of 1 kg to have an acceleration of 1 m/s^2. If a force of 5 newtons is applied to a mass of 5 kg, what will be its acceleration? A.) 1 m/s^2 B.) 25 m/s^2 C.) 5 m/s^2 D.) 0.20 m/s^2

Explain why the car reaches a top speed even though the thrust Force remains constant at 3500N

4. A helicopter is flying at a height of 1.5km. If it has 50MJ of G. P. E., what is the mass of the helicopter?

Unless otherwise posted, what is the speed limit in a school zone? florida

If you put in 10 J of work to push 1 c of charge against and electric field what will be its voltage with respect to its starting position? when released, what will be it's kinetic energy if it flies past it's starting position?

The process of changing the energy of a system by means of force. Force * Diatance