Why do tectonic plates move?

Why Galileo's thought experiment about the ball rolling forever on a level surface could only be a thought experiment.

If you have a temporary illness that may affect your ability to drive, you should: A. Determine your own fitness for driving B. Obtain a restricted drivers license C. Only drive when you're heavily medicated

How many atoms at in a pencil

Where does the water come from?

Under normal conditions, you are just barely able to lift a mass of 74 kg. Your friend drops a box of volume 2.4 m3 into a lake. If you are just able to lift it to the surface (so that it is still completely submerged), what is the mass of the box

Imagine two artificial satellites orbiting earth at the same distance. one satellite has a greater mass then the other one which of the following would be true about there motion? 1.

What is energy? (Not the answer from google search.)

Explain why the friction force between two surfaces increases if the force is pushing the surfaces together increases.

As energy moves in waves through the water, the water moves a. in waves toward shore. c. in the direction of the waves. b. in a small circular movement. d. against the current.

Which of the following values represents an index of refraction of an actual material? A. 0 B. 1 / 4 C. 5 / 4 D. 1 / 2