In an experiment the angles are required to be measured
Question:

In an experiment the angles are required to be measured using an instrument 29 divisions of the main scale exactly coincide with the 30 divisions of the vernier scale. If the smallest division of the main scale is half-a-degree $\left(=0.5^{\circ}\right)$, then the least count of the instrument is :-

1. One degree

2. Half degree

3. One minute

4. Half minute

Correct Option: , 3

Solution: