Choose the best definition for velocity

1. How fast something is going

2. Speed in a certain direction

3. Which direction something is going

4. Something speeding up

Is science open to change (can scientific therories change) if new evidence is presented

What simple machine would move or turn an object? wheel and axle lever screw wedge

2 ways radio waves and gamma waves are alike

Which type of energy is released when a nucleus is split apart? O A. Chemical energy O B. Nuclear energy O C. Elastic energy O D. Kinetic energy

Astronomers believe that cosmic background radiation formed: a. about 1 billion years ago. b. about 1 million years ago. c. shortly after the big bang. d. about 100,000 years ago.

Is the following sentence true or false? Some information about an object or process may be missing from a model.

If V is a velocity, l a length, and v a fluid property having dimensions of L2T-1, which of the following combinations are qualitatively dimensionless (show work for a through d) : (a) V l v (b) Vl/v (c) V2v (d) V / (l v)

What happens to the total mechnical energy of the apple as it falls from the tree?

Fair Bonus Question: Derive the equation for gravitational potential energy, starting with the definition of work.

A juggler throws a bowling pin into the air with an initial velocity. Another juggler drops a pin at the same instant.