Question

Spring balance is used for measuring

• A. The force acting on an object
• B. The force of friction
• C. Magnitude of the pressure
• D. Relative motion between the object

Answer 1

The correct option is A

The force acting on an object

Explanation of correct option

1. Spring balance is a mechanical device used to measure the weight of an object opposing the force of gravity.
2. The basic working principle behind spring balance is Hook's law.
3. According to Hook's law, the elongation of the spring is directly proportional to the load applied to the spring.
4. That is $F=-kx$ where $F$ is the load attached, $k$ is the spring constant and $x$ is the elongation of the spring.
5. So spring balance is used to measure the force acting on the object.

Hence, option A is correct.