Physics
Assertion (A): A fuse wire must have a high resistance and low melting point.
Reason (R): A fuse is only used for a small current flow.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true and R is not the correct explanation of A.
- assertion is false but reason is true.
- assertion is true but reason is false.
Answer
assertion is true but reason is false.
Explanation
Assertion (A) is true. A fuse wire must have a high resistance to generate enough heat when a high current flows through it, causing it to melt and break the circuit.
Reason (R) is false. While fuses are used for protecting electrical circuits, they are not specifically used only for small current flow. Fuses are designed to handle normal operating currents but melt and break the circuit when the current exceeds a safe level, regardless of whether it is small or large.
Related Questions
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Reason (R): As the hammer starts falling, its kinetic energy begins to change into potential energy.
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Reason (R): This is because the effort arm is always greater than the load arm.
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Reason (R): The specific heat capacity of a substance is not its characteristic property.
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