What is the definition for energy?

A hiker determines the length of a lake by listening for the echo of her shout reflected by a cliff at the far end of the lake. She hears the echo 2.1 s after shouting. The speed of sound in air is 343 m/s. Determine the length of the lake.

The law of suggests that the orbit of planets is not circular but.

When atoms form a bond, it is usually because each atom acquires a more stable arrangement of electrons in its electron shells. What is the best description of this arrangement of electrons? A. All shells have the same number of electrons. B.

How do electric motors create movement? A. by harnessing gravitational potential energy B. by using electrically-produced magnetic fields C. by electric current through turbine blades D. by spinning magnets to induce electric current

a 85 Kg girl, running 1.5 m/s, runs for 2550 seconds. How much force is required to stop her in 5 seconds

A 125-kg merry-go-round in the shape of a uniform, solid, horizontal disk of radius 1.50 m is set in motion by wrapping a rope about the rim of the disk and pulling on the rope.

Jose wandered 4 kilometers at 2 kilometers per hour. How long did Jose wander?

What is the acceleration of a 10kg pushed by a 5n force

A device that changes thermal energy into mechanical energy

You and your roommate are moving to a city 380 mimi away. Your roommate drives a rental truck at a constant 55 mi/hmi/h, and you drive your car at 65 mi/hmi/h. The two of you begin the trip at the same instant.