Why doesn't the magnetic force change the velocity of a particle?

Well actually, it does. Remember that the velocity is a vector and so is the force. Since F=ma, the acceleration due to a given force points in the same direction as the force itself. The magnetic force is perpendicular to the direction of motion, and hence so will the acceleration. And we know that when the acceleration is perpendicular to the velocity of a particle, it undergoes uniform circular motion. So, the magnitude of the velocity remains unchanged when the particle is acted upon solely by a magnetic force. Yet, as we just said, the velocity is a vector and hence it is defined by both is magnitude and direction. Since the direction changes, the velocity vector also does change. We call such an acceleration (which is always perpendicular to the velocity) normal or centripetal, as it makes the particle circle around a certain point.

AS
Answered by Ana S. Physics tutor

2933 Views

See similar Physics GCSE tutors

Related Physics GCSE answers

All answers ▸

What are the differences between microwaves and radio waves? How does this effect what we use them for?


Explain the difference between a longitudinal and transverse wave.


Trolley A weighs 5kg and is moving at 15m/s to the right. It collides with a stationary Trolley B, weighing 10kg more than Trolley A. After the collision they move off together. Calulate the velocity that they move off with.


An elastic wire suspended from a workbench has a 2kg mass attached to its free end. The wire changes in length by 2cm. Calculate the elastic potential energy stored in the wire.


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences