How much work is required to stop an electron (m = 9.11 10-31 kg) which is moving with a speed of 2 106 m/s?
To calculate the amount of work required to stop an electron, we need to use the formula for work. Work is defined as the product of force and displacement. In this case, the force required to stop the electron is equal to the momentum change of the electron.
The momentum of an object is given by the formula p = mv, where p represents momentum, m is the mass, and v is the velocity. Therefore, the momentum of the electron is:
p = (mass of electron) x (velocity of electron)
= (9.11 x 10^-31 kg) x (2 x 10^6 m/s)
= 1.822 x 10^-24 kg*m/s
Since the electron needs to be stopped, its final velocity will be zero. Therefore, the change in momentum will be equal to the initial momentum. Now, we can calculate the work using the formula:
Work = force x displacement
Force = change in momentum / time
Displacement = 0 (since the electron will end up at rest)
Time = unknown (we don't have this information)
Therefore, without knowing the time, we cannot accurately calculate the work required to stop the electron.