Question

Which of the below-given instruments has 0.01 mm as its least count?

• A. Screw gauge
• B. Vernier Caliper
• C. Thermometer
• D. None of the above

Answer 1

The correct option is A

Screw gauge

Step 1: Explanation of the correct option

In the case of option A

1. A screw gauge is a tool for precisely measuring the thickness of a metal sheet or the diameter of a thin wire.
2. The smallest value that a measuring instrument can measure is referred to as its least count.
3. It can be calculated by dividing the screw pitch by the number of divisions on a circular scale.
4. The least count of a screw gauge is 0.01 mm.

Step 2: Explanation for the incorrect options

In the case of option B

1. A Vernier Caliper is a measuring tool used to determine the width, height, and radius of a body.
2. It has the least count of $0.1\mathrm{mm}$.

In the case of option C

1. The thermometer is an instrument that is used for measuring the temperature of a body.
2. There are three units that are commonly used for measuring the temperature of a body. They are Celsius, Fahrenheit, and kelvin.

In the case of option D

Since the correct answer is available in the given option so none of the above is not the case here.

Hence, option A is the correct answer.