Is energy absorbed or given off when an electron and a hole of a semi-conductor crystal

recombine? What are the forms of energy that can be absorbed or given off?

As the temperature of the water gets colder, the speed of its molecules:

Which statement best describes why a machine is useful?

What happens to the charge lost by an object?

Which of the following is the best example of Newton's second law? A. A rolling ball comes to a stop because the forces of friction and gravity are acting upon it. B.

Can an object have kinetic and potential energy at the same time

You are in the lab and are given two rods set up so that the top rod is directly above the bottom one. The two straight rods 50-cm long are separated by a distance of 1.5-mm each with 15 A of current passing through them.

What is the explanation for feather beds being warm

A student wearing frictionless in-line skates on a horizontal surface is pushed by a friend with a constant force of 47 N. How far must the student be pushed, starting from rest, so that her final kinetic energy is 354 J?

Suppose a rocket ship in deep space moves with constant acceleration equal to 9.8 m/s2, which gives the illusion of normal gravity during the flight.

A canoeist on a lake throws a 0.145 kg baseball at 20.0 m/s to a friend in a different canoe. Each canoe with its contents has a mass of 120 kg, and is at rest initially.