In order for energy to be conserved, what must happen

A 700-watt gasoline engine and a 300-watt electric motor both do 3 J of work. Which machine can do the work faster? Explain your answer.

What type of electromagnetic radiation travels the fastest? a) radio waves b) sound waves c) X-rays d) infrared rays e) All of the above

A ball is dropped from rest. What will be its speed when it hits the ground in each case. a. It is dropped from 0.5 meter above the ground. b. It is dropped from 5 meters above the ground. c. It is dropped from 10 feet above the ground.

At what height h above the ground does the projectile have a speed of 0.5v? Express your answer in terms of v and the magnitude of the acceleration of gravity g.

Is it true that any marking on an angle means that the angle measure 90 degrees?

In order for convection to occur, you must have

Explain Newton's First Law for the following. If you walk across the room holding a ball, when should you drop it to ensure that it lands on a target? Before, after or when you are directly on the target?

In what way are all forms of potential energy the same?

Enise is riding her bike and falls to the ground. During the collision, she hits both grass and cement. Which best explains why Denise had fewer injuries to the area of her body that hit the grass?

A rock is dropped into the Grand Canyon. It takes 18 seconds to hit the bottom. Calculate how deep the canyon is.