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A uniform electric field and uniform magnetic field are acting along the same direction in a certain region. If an electron is projected in the region such that its velocity is pointed along the direction of fields, then the electron
- will turn towards right of direction of motion
- speed will decrease
- speed will increase
- will turn towards left direction of motion
Correct answer: speed will decrease
Solution
The electric field exerts a force on the electron opposite to its velocity, causing its speed to decrease. The magnetic force is zero because the velocity is parallel to the magnetic field.
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