An object moves in a circle. If the mass is tripled, the speed halved, and the radius unchanged then the centripetal force must change by a factor of:

3/2

3/4

9/4

6

12

An engine manufacturer makes the claim that the engine they have developed will, on each cycle, take 100J of heat out of boiling water at 100∘C, do mechanical work of 80J, and exhaust 20J of heat at 10∘C. What, if anything, is wrong with this claim?

A flat metal washer is heated. As the washer's temperature increases, what happens to the hole in the center? A flat metal washer is heated.

The aluminum foil in a package containing 75 square feet of foil weighs 12 ounces. aluminum has a density of 2.70 g / cm3. what is the approximate thickness of the foil in mm?

Which of the following will cause acceleration? A. maintaining constant velocity B. moving in one direction only C. the presence of unbalanced forces acting on an object D. two forces of equal magnitude and opposite directions acting on an object

NASA launches a satellite into orbit at a height above the surface of the Earth equal to the Earth's mean radius. The mass of the satellite is 780 kg. (Assume the Earth's mass is 5.97 1024 kg and its radius is 6.38 106 m.

In pottery class, you throw a pot from a lump of wet clay. your pot's mass is 5.5 kg. after the pot is fired, it's mass is 4.9 kg. the density of wet clay is 1.60 g/cm3 and the density of fired clay is 1.36 g/cm3.

When you catch a baseball, what kind of work do you do, negative or positive? By catching the baseball, what do you change? Does the baseball gain or lose energy? What kind of energy?

A man finds that he has a mass of 100.6 kg. He goes on a diet, and several months later he finds that he has a mass of 96.4 kg. Express the mass 100.6 kg in scientific notation.

A bird has a kinetic energy of 3 J and a potential energy of 25 J. What is the mechanical energy of the bird?

Material A has a higher thermal conductivity than Material B. Which material will transfer energy by conduction faster?