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.

  • Google+ icon
  • LinkedIn icon
  • 788 views

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 Tq = 1.6 x 10-19 (the charge of an electron) and v = 2 x 10ms-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!)

Sally H. A Level Maths tutor, IB Maths tutor, GCSE Maths tutor, 11 Pl...

About the author

is an online A Level Physics tutor who has applied to tutor with MyTutor studying at Bristol University

Still stuck? Get one-to-one help from a personally interviewed subject specialist.

95% of our customers rate us

Browse tutors

We use cookies to improve your site experience. By continuing to use this website, we'll assume that you're OK with this. Dismiss

mtw:mercury1:status:ok