40 newton’s•meters of torque is required to close a door 1.8 meters wide. what force is needed to cause this torque?

In a classical model of the hydrogen atom, the electron moves around the proton in a circular orbit of radius 0.053 nm. what is the electron's orbital frequency? what is the effective current of the electron?

The built in flash in a compact camera is usally capable of giving correct exsposure for distance up to how many meters?

If it takes ashley 3 seconds to run from the batters box to first base at an average speed of 6.5 meters per second, what is the displacement she covers in that time?