What is the acceleration of the object?

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?

Distinguish between linear momentum and angular momentum

Acamcorder has a power rating of 20 watts. if the output voltage from its battery is 9 volts, what current does it use?