Question

The screw gauge is used to measure the diameter of a
A. Crowbar
B. Thin wire
C. Cricket ball
D. None

Answer 1

Hint: A screw gauge is an instrument that is used for measuring the diameter of thin wires and also the gauge can be used for measuring the thickness of thin metal sheets. Screw gauge has the smallest least count therefore it can be used to measure small measurements.

Complete step by step answer:
Let us consider each option and see which instrument is used to measure the diameter of each of these objects.

Let us consider the first option,
Crowbar: A crowbar is a tool that has a single curve end having flattened points; the tool is too large to be measured by the screw gauge.

Let us consider the second option,
A thin wire is having a very small diameter and screw gauge is suitable for the measuring of the diameter of thin wires as well as the width of sheet metals.

Let us consider the third option,
Cricket ball: A cricket ball has a large cross-section area as compared to the thin wire, therefore; it cannot be measured by screw gauge. The diameter of a cricket ball can be calculated by measuring the circumference of the ball and after using the formula of \[C = 2\pi r\]. We can calculate the value of the radius of the cricket and hence the diameter of the cricket ball.

The fourth option is none which cannot be correct because the second option which is correct for this problem, which says that screw gauge, is used for the measurement of the diameter of thin wire.

Therefore, Option (B) is the correct option.

Note:
Students should observe that the screw gauge is an instrument which is used to measure the small thickness. It is advisable for students to not confuse the screw gauge with the vernier caliper as the screw gauge is used only for external measurement whereas the vernier caliper is can be used for internal as well as external measurement also the least count of vernier caliper is $0.01\, mm$ and the least count of the screw gauge is $0.001 mm$.