Physics
The above circuit diagram illustrates a copper bar placed on two copper wires stretched over a wooden base placed between two poles of magnets. This entire setup is placed on a compression balance, which shows a weight of 0.4 kgf.
(a) What will be the observation of the compression balance when we close the switch?
(b) How will this observation change, when we increase the current in the circuit?
(c) Name the rule used to come to the conclusion in (a).
Answer
(a) The reading on the compression balance will increase.
(b) The reading on the compression balance will increase.
(c) Fleming’s left-hand rule.
Explanation:
When the switch is closed, current flows through the copper bar in a magnetic field. This causes a Lorentz force (also called the magnetic force) to act on the conductor. This force is perpendicular to both the direction of current and the magnetic field. Due to this, the copper bar experiences a downward force, causing the compression balance reading to increase.
Related Questions
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(c) Give reasons for your answer.
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