Find the magnitude of the force on an electron that is travelling with velocity 2 x 10^4 ms^(-1) in the x direction through a uniform magnetic field of strength 2T in the y direction.

This question tells us we only need to consider the magnitude of the force, and since the magnetic field and electron's velocity are perpendicular, we can simply use the equation

F = Bqv.

We have B = 2 T, q = 1.6 x 10-19 C (the charge of an electron) and v = 2 x 104 ms-1.

Substituting these values into the equation gives 

F = 2 * (1.6  x 10-19 ) * (2 x 104) = 6.4 x 10-15 N   (Remember your units!)

SH

Related Physics A Level answers

All answers ▸

A cannon ball is shot at an angle of 60 degrees from a cliff of height 50m, if it's inital speed is 20ms^-1 what horizontal distance does it travel before hitting the ground.


Where does the simple harmonic motion equation come from and what does it mean?


A piece of card is released from rest at a height of 0.5m above a light gate. It falls freely and a computer measures the velocity as it passes through the light gate to be 3.10m/s. What is the acceleration due to gravity measured by this experiment?


If a car is travelling over a curved hill, what is the maximum speed it can travel before losing contact with the road surface?