The device used to convert mechanical energy into electrical energy is MCQ with Answer and Explanation

Explanation:
A fuse is an electrical safety device consisting of a wire made of an alloy with a low melting point. If the current exceeds a safe limit (due to a short circuit or overload), the Joules heating (I²Rt) causes the wire to melt instantly, breaking the circuit and preventing fire or damage to appliances.

Explanation:
Beat frequency is the absolute difference between two frequencies. Given 4 beats with 256 Hz, the unknown fork is either 256+4=260 Hz or 256-4=252 Hz. Adding wax increases mass, which strictly lowers the frequency of a fork. If it was 252 Hz, lowering it would increase the gap from 256, increasing beats. If it was 260 Hz, lowering it brings it closer to 256, decreasing beats to 2. Thus, it was originally 260 Hz.

Explanation:
Ammeter measures current, must be in series so same current flows through it. Low resistance minimizes circuit disturbance. Voltmeter connects in parallel. Memory aid: 'Ammeter = series (low R); Voltmeter = parallel (high R)'. Circuit connection rule frequently tested in competitive electricity sections.