Question

Which of the following instruments make use of the principle of moments during operation?
A. Rule
B. Vernier calipers
C. Spring balance
D. Simple balance

Answer 1

Hint: This question explains how movement around a fixed point and axis can be measured with forces acting on both ends of an object, most especially objects that swing back and forth. Principle of moments states that when a body is in balanced position, the total clockwise moment about a point is equal to the anticlockwise moment about the same point.

Complete step by step answer:
Rule or ruler is used to measure distance between two or more points.
Vernier calipers are used to measure internal dimensions, external dimensions, depth and height of objects like pipes, spheres etc.
The spring balance is used to measure the weight of an object with a measurement scale or a calibration at the centre with most times the spring hooks or baits the material or the object to be measured.
Simple balance works principally or majorly on the principle of moments where both sides and ends are loaded with the centre fixed as the principle of moment states that the algebraic sum of moment in the anticlockwise (the side opposite the direction of time) is equal to the algebraic sum of moment in the clockwise direction (the side in the direction of time).
Therefore, the correct option is Option D, Simple balance makes use of principle of moments during operation.

Note:Moment can be also found when a boy and a girl decides to sit on both ends of a plank which is placed on a rigid or firm iron, the light weight boy or girl will tint or incline upwards while the heavier boy or girl will incline downwards. And do not confuse movement with torque as torque is used when there is an involvement of rotations and moment is used when there is no rotation.