H C Verma Solutions for Chapter: Speed of Light, Exercise 1: QUESTIONS FOR SHORT ANSWER

The speed of sound in air is $332 \mathrm{m} {\mathrm{s}}^{-1}$. Is it advisable to define the length $1 \mathrm{m}$ as the distance travelled by sound in $\frac{1}{332} \mathrm{s}$ ?

Consider Galileo's method of measuring the speed of light using two lanterns. To get an accuracy of about $10\%,$ the time taken by the experimenter in closing or opening the shutter should be about one tenth of the time taken by the light in going from one experimenter to the other. Assume that it takes $\frac{1}{100}$ second for an experimenter to close or open the shutter. How far should the two experimenters be to get a $10\%$ accuracy? What are the difficulties in having this separation?

In Fizeau method of measuring the speed of light, the toothed wheel is placed in the focal plane of a converging lens. How would the experiment be affected if the wheel is slightly away from the focal plane?

In the original Fizeau method, the light travelled $8.6$ $\mathrm{km}$ and then returned. What could be the difficulty if this distance is taken as $8.6 \mathrm{m}$

What is the advantage of using a polygonal mirror with larger number of faces in Michelson method of measuring the speed of light?