Electric Circuit

An ammeter is a device used to measure electric current in a circuit.
A galvanometer is a sensitive instrument that detects and measures small currents.
Therefore, both ammeter and galvanometer measure the same physical quantity, i.e., electric current.

Note: While the ammeter measures larger currents and is used in series in circuits, the galvanometer is used for detecting smaller currents with high sensitivity.

The correct option is (B): Ammeter, galvanometer

The formula for electrical energy is: where:
is the energy in joules,
is the potential difference in volts,
is the charge in coulombs.
Substituting the given values:

Thus, the correct answer is 12 joules.The correct option is (D): joules

The area under a current-time graph gives the electric charge. This is because electric charge is related to current and time by the formula: Thus, the area under the current-time graph represents the total electric charge.

The correct option is (D): electric charge

An electric fuse is a safety device used in household circuits to prevent damage caused by overloading or excessive current. It is designed to break the circuit when the current exceeds a safe level, thus protecting the electrical appliances from potential damage. Thus, the correct purpose of an electric fuse is preventing damages due to overloading.

The correct option is (C): preventing damages due to overloading