A uniform electric field and a uniform magnetic field are produce… - Vidyadip

MCQ

A uniform electric field and a uniform magnetic field are produced, pointed in the same direction. An electron is projected with its velocity pointing in the same direction

A
The electron will turn to its right
B
The electron will turn to its left
C
The electron velocity will increase in magnitude
✓
The electron velocity will decrease in magnitude

✓

Answer

Correct option: D.

The electron velocity will decrease in magnitude

d
(d) Since electron is moving is parallel to the magnetic field, hence magnetic force on it ${F_m} = 0$.
The only force acting on the electron is electric force which reduces it’s speed.

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