# Class 11 Physics Practical - To determine volume of an irregular lamina using screw gauge, Viva Questions with Answers

1) What is a screw gauge?

A measuring device made out of a calibrated screw is called a screw gauge, which is also known as a micrometre. It is used to measure the dimensions of small objects. It is basically a type of meteorological instrument used in machining, mechanical engineering, and several other applications.

2) What are the different types of motion owned by a screw?

There are basically two types of motion that a screw possesses, and they are:

(i) Possessed by the axis, called the linear motion.

(ii) Possessed by the surface, called the circular motion

3) What is the pitch of a screw gauge?

In one complete rotation, the distance moved by the screw is known as its pitch.

4) What do you mean by the least count of a screw gauge?

When turned through one division of the head scale, the distance moved by the tip of the screw is known as the least count of the screw.

LC (Least count) of a screw gauge can be calculated as the pitch of the screw gauge divided by the total number of divisions on the circular scale:

LC (Least count) of micrometre (screw gauge) = (1 mm)/ (100) = 0.01 mm

5) What are the reasons for zero error?

The reasons for zero error are:

1. Wear and tear of the screw
2. Manufacturing defect

6) How can one avoid backlash errors in a screw gauge?

Backlash error can be avoided by always turning the screw in the same direction and by applying small lateral pressure on the screw.

7) What is the least count of Vernier calliper?

The least division on the main scale divided by the number of divisions on the Vernier scale is the least count of a Vernier calliper.

Therefore, the least count of Vernier calliper is = 0.1 mm, that is, (1mm/10 divisions)

8) Define 1 metre.

By definition, 1 metre is the distance travelled by the light in a vacuum in 1/299792458 seconds.

9) What is the difference between mass and weight?

Weight is the acceleration due to gravity; the measurement of the amount of force acting on a mass is known as weight, which is generally denoted by W, and the measure of the amount of matter present in a body is known as its mass denoted by M.

10) Name the metal which is used to make a screw gauge.

Gunmetal is used to make a screw gauge.