Which of the following is a good thermal insulator?*

Iron

Styrofoam

Silver

Graphite

A student is standing in an elevator that is accelerating upward. the force that the student exerts on the floor of the elevator must be

light spring of force constant k = 158 N/m rests vertically on the bottom of a large beaker of water (Figure a). A 4.

Which of the following is not a simple machine? A. tape B. lever C. screw D. inclined plane

That's because helium molecules are not packed together as densely as air molecules are. It is this simple reason that helium balloons float in the air.

A wave has a wavelength of 3.0m and a frequency of 400mHz. Calculate its speed.

3. Calculate the amount of current through a 45-watt light bulb that is connected to a 120-volt circuit in your home.

Are oranges called oranges because oranges are orange, or is orange called orange because oranges are orange?

An object at rest has no net force acting on it. a. True b. False

A baseball has mass 0.145 kg. (a) If the velocity of a pitched ball has a magnitude of and the batted ball's velocity is in the opposite direction, find the magnitude of the change in momentum of the ball and of the impulse applied to it by the bat.

A long distance runner has an average speed of 4m/s during a race. How far does the runner travel in 20 minutes?