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A uniform electric field and a uniform magnetic field are acting along the same direction in certain region. If an electron is projected in the region such that its velocity is pointed along direction of fields, then the electron:

  1. A
    Will turn towards left of direction of motion
  2. B
    Will turn towards right of direction of motion
  3. C
    Speed will decrease
  4. D
    Speed will increase

Solution & Step-by-step Explanation

1. Magnetic Field Force: . Since , . No magnetic force.2. Electric Field Force: . Since is along velocity, the force on the electron is in the opposite direction.This decelerating force will cause the speed of the electron to decrease.

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A uniform electric field and a uniform magnetic field are acting along the same direction in certain region. If an electron is projected in the region such that its velocity is pointed along direction of fields, then the electron:
A
Will turn towards left of direction of motion
B
Will turn towards right of direction of motion
C
Speed will decrease
D
Speed will increase

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