Question

A 10 ev electron is circulating in a plane at right angles to uniform field of magnetic induction 10^-4 wb/m^2

Answer 1

Answer :-

Kinetic energy of electron (12×mv2)=10eV

and magnetic induction (B) = 10−4Wb/m2

Therefore 12(9.1×10−31)v2=10×(1.6×10−19)

or, v2=2×10×(1.6×10−19)9.1×10−31=3.52×1012

or , v=1.876×106m

Centripetal force = mv2r=Bev.

Therefore r=mvBe=(9.1×10−31)×(1.876×106)10−4×(1.6×10−19)

=11×10−2m=11cm