Important Questions Test: Electric Current & its Effects - Class 7 MCQ

An electric cell is depicted by a longer line for the positive terminal and a shorter, thicker line for the negative terminal in circuit diagrams.

A battery stores chemical energy and releases it as electrical energy, providing power to various devices in the circuit.

The filament in a bulb heats up due to the electric current, producing light.

LED bulbs use electroluminescence to produce light without generating significant heat, unlike devices like hairdryers or toasters that use heating elements.

MCBs are automatic switches that cut off the current during overloads or short circuits, making them more reliable and easy to reset than fuses.

A switch controls the flow of electric current by either opening (stopping current) or closing (allowing current to pass) the circuit.

The electric bell works on the magnetic effect of electric current, where an electromagnet pulls a metal strip to produce sound.

An ammeter is used to measure electric current in a circuit. It is connected in series with the components to measure the current flowing through them.

A coil of wire around an iron core that becomes magnetic when current flows through it is known as an electromagnet.

Plastic is an insulator and does not conduct electricity, unlike copper, aluminum, and iron, which are conductors.