Trevor lifts a 10kg box to the top of a cliff which is 20m high, in half an hour, then drops the box over the cliff. How much power did he use to lift the box?

When light hits a mirror it bounces off of it. This is why you can see yourself in a mirror. This property of light is A) absorption. B) reflection. C) refraction. D) transparent.

6. The four main systems of the Earth are A. geology, meteorology, oceanography, and chemistry. B. geosphere, atmosphere, hydrosphere, and aerosphere. C. aromatherapy, biology, chemistry, and physical properties. D.

A typical set of stairs is angled at 38∘. You climb a set of stairs at a speed of 3.3 m/s. 1). How much height will you gain in 3.6 s? 2). How much horizontal distance will you cover in 3.6 s?

If a passenger train is traveling on a straight track with a negative velocity and a positive acceleration, is it speeding up or slowing down?

List and describe the forces that act on a block as it moves down the ramp at constant speed.

A geologist estimates that a large boulder weighs 7840 N. What should he estimate the mass of this boulder to be? A. 650 kg B. 740 kg C. 780 kg D. 800 kg

Two objects have the same momentum. Do the velocities of these objects necessarily have (a) the same directions and (b) the same magnitudes? Give your reasoning in each case.

If you keep voltage constant and increase resistance resistance, what happens to current?

A scene in a movie has a stuntman falling through a floor onto a bed in the room below. The plan is to have the actor fall on his back, but a researcher has been hired to investigate the safety of this stunt.

During energy transformation, all energy systems: are a. 100 percent efficient b. lose energy c. gain heat energy d. create energy