In order to change water from a solid to a liquid, energy must be

a. removed

b. created

c. added

d. destoryed

A 2.0 kilogram ball above the floor has 39 joules of potential energy the balls height is about meters above the floor

Write the differences between evaporation and boiling? (AS1)

When starting a foot race, a 70.0kg sprinter exerts an average force of 650 N backward on the ground for 0.800 s. How far does he travel? a) 1.48 m (b) 2.97m (c) 5.95 m (d) 11.9m

A molecule that speed up a reaction

A small bolt with a mass of 33.0 g sits on top of a piston. The piston is undergoing simple harmonic motion in the vertical direction with a frequency of 3.05 Hz.

Why is copper a good conductor?

Sketch of the distance vs time graph for a car with constant velocity

3. Applying Concepts Explain why a canoe that has hollow, water- tight compartments on its ends won't sink, even if it is capsized.

If two forces of equal magnitude act on an object that is hinged at a pivot, the force acting farther from the pivot must produce the greater torque about the pivot. A) true B) false C) unable to decide without knowing the shape of the object

Standard voltage for electrical circuits in the United States is 120 volts. Is this the standard voltage in other countries?