Join the Most Relevant JEE Main 2025 Test Series & get 99+ percentile! Join Now
Search any question & find its solution
Question: Answered & Verified by Expert

A block of mass m and charge q is released on a long smooth inclined plane. Magnetic field B is constant, uniform and out of the plane of the paper as shown. Find the time from the start when blocking lose contact with the surface.

PhysicsMagnetic Effects of CurrentJEE Main
Options:
  • A mcosθqB
  • B m cosec θqB
  • C mcotθqB
  • D mtanθqB
Solution:
1688 Upvotes Verified Answer
The correct answer is: mcotθqB

Block will lose contact with surface when force due to magnetic field will become equal to mgcosθ

qvB=mgcosθ

v=mgcosθqB=u+at ( along inclined plane )

v=mgcosθqB=(g sinθ)t     

t= m cotθqB

Looking for more such questions to practice?

Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.