JEE Main & Advanced Physics Current Electricity, Charging & Discharging Of Capacitors / वर्तमान बिजली, चार्ज और कैपेसिटर का निर Question Bank Assertion and Reason

  • question_answer
    Assertion             :       Fuse wire must have high resistance and low melting point. Reason                 :   Fuse is used for small current flow only.

    A)             If both assertion and reason are true and the reason is the correct explanation of the assertion.

    B)             If both assertion and reason are true but reason is not the correct explanation of the assertion.

    C)             If assertion is true but reason is false.

    D)             If the assertion and reason both are false.

    E)             If assertion is false but reason is true.

    Correct Answer: C

    Solution :

                Assertion is true but reason is false. Fuse wire must have high resistance because in series current remains same, therefore according to Joule's law \[H=\frac{{{i}^{2}}Rt}{4.2}\], heat produced is high if R is high. The melting point must be low so that wire may melt with increase in temperature. As the current equal to maximum safe value, flows through the fuse wire, it heats up, melts and break the circuit.


You need to login to perform this action.
You will be redirected in 3 sec spinner