What is the hardness of copper ore?

A lever has a total length of 12 meters with a fulcrum at the exact center of the lever. Which best describes how to double the mechanical advantage of the lever?

A bowling ball is dropped from a height of 24 feet. a. Write a function that gives the height h (in feet) of the bowling ball after t seconds. h (t) = ? b. Find the height of the bowling ball after 1 second.

A 72 kg sled is pulled forward from rest by a snowmobile and accelerates at 2.0m/s^2 (forward) for 5.0 seconds. The force of friction acting on sled is 120 N (backwards). The total mass of a snowmobile and driver is 450 kg.

820 mol of hydrogen gas hydrogen gas has a volume of 2.00 l at a certain temperature and pressure. what is the volume of 0.125 mol of this gas at the same temperature and pressure

If you drew magnetic field lines for this bar magnet, which statement would be true

Gravity pulls gases and dust particles in space toward one another, squeezing them into a smaller and smaller space. The temperature at the center rises high enough for fusion of hydrogen to begin.

Which has greater kinetic energy: a bullet that has a mass of 0.05 kg travelling at 2500 m/s, or a lorry that has a mass of 4500 kg and is moving at 50 m/s?

Bio mass, sun, wind, water

What is the mass of 5 moles of gold

A crane lifts a 400 N crate full of baked beans 15 m. How much work was done by the crane?