MCQ
How will two parallel beams of electron behave while moving in the same direction?
- ARepel each other
- BAttract each other
- CNot interact with each other
- DAnnihilate each other
✓
Answer
- Attract each other
Explanation:
Two parallel beams of electron moving in the same direction can be think of like two current carrying wire in same direction.
The situation is shown in the figure. The direction indicated shows that wire 2 will be attracted towards wire 1. In a similar manner, one can show that wire 1 will experience a force due to the magnetic field of wire 2, and that this force will have a magnitude equal to that of F2 but opposite in direction. Thus, wire 1 will be attracted towards wire 2.
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