COMEDK Exam 2017 Solved Paper

Given, electric field, E=1500V∕m
Magnetic field, B=0.4‌Wb∕m2
Charge on electron, q=e=1.6×10−19C
For minimum uniform speed of electron along a straight line is a region, where electric field E and magnetic field B, both are present is given as
‌v=‌

E

B

‌‌[

∵qE=Bqv

⇒v=‌ E B

]
‌=‌

1500

0.4

‌=3750m∕ s
‌=3.75×103m∕ s