Physics
The given figure shows the path of three particles A, B and C in a uniform magnetic field (perpendicular to the plane of paper outwards). Identify the nature of charges on them. Name the rule you have used
Answer
- Particle A is negatively charged.
- Particle B is uncharged (neutral).
- Particle C is positively charged.
Rule used: Fleming's left-hand rule
Explanation:
According to Fleming's left-hand rule:
- Forefinger shows the direction of magnetic field,
- Middle finger shows the direction of current,
- Thumb shows the direction of force.
Here, the magnetic field is out of the plane of the paper and the particles move towards the right.
For a positive charge, the current is taken in the direction of motion. So, on applying Fleming's left-hand rule, the force acts downwards.
Therefore:
- C, which deflects downwards, is positively charged.
- A, which deflects upwards, is negatively charged, since a negative charge is deflected opposite to a positive charge.
- B remains undeflected, so it is uncharged.
Related Questions
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