For an atom's electrons, how many energy sub levels are present in the principal energy level n = 4?

How much force is required to accelerate a 50 kg with a mass at 4 m/s2?

A hammer is dropped from the roof of a building 1000 meters tall. How long will it take to hit the ground?

Why would you want a gold ring rather than a copper ring? (I know gold is more valuable)

A rock and a feather are dropped from the rooftop of a building. which has more kinetic energy

Which unit is used to measure force

Protons and neutrons strongly attract when they

How far is Jupiter from the sun?

Steam moves into a cylinder of a steam engine at a constant pressure and does 2.34 J of work on a piston. The diameter of the piston is 3.4 cm and the piston travels 4.6cm. What is the pressure of the steam?

Identify each type of simple machine.

A car's speedometer reads 20 m/s after accelerating, from a standing start, for 25s. What was the magnitude of its acceleration?