If I assume you are talking about on Earth, then by using the equation
Weight Force=mg
382=(10)m
m=382/10
m=38.2 kg
Note that regardless of whether you are on Earth or any other planet or body the mass of something does not change. Only the weight of it changes as the gravitational acceleration (g) varies from planet to planet.
the emf generated by a magnetic coil of the generator, because it consists of a coil turning in a magnetic field; it opposes the voltage powering the motor, so at first the current reaches 10A but subsequently due to the back emf generated in the coil this emf opposes the self induced emf thereby reducing the current to 4A