Find the ratio of the lengths of simple pendulum and second's pendulum.

Calculate the dimension of a cube from the given data of readings using a vernier calliper. In the main scale $1 \mathrm{cm}$ is divided into $20$ parts.
Number of divisions on the vernier scale$=25$; Zero error$=-0.016 \mathrm{cm}$
When the cube is held between the jaws, the position of the zero of the vernier callipers is between $2.75 \mathrm{cm}$ and $2.8 \mathrm{cm}$ and the coinciding division of vernier callipers is $9^{\mathrm{th}}$.

A fat boy on a diet lose $2.3 \mathrm{kg}$ per week. Express the mass loss rate in $\mathrm{mg}/\mathrm{s}$ if the fat boy could sense the loss second by second.

$$\begin{gathered} \mathrm{A} : 0.386 \mathrm{mg}/\mathrm{s} \\ \mathrm{B} : 0.0386 \mathrm{mg}/\mathrm{s} \\ \mathrm{C} : 0.386 \mathrm{g}/\mathrm{s} \end{gathered}$$

Enter your correct answer as $\mathrm{A}, \mathrm{B} \mathrm{or} \mathrm{C}$.

The thimble of a screw gauge has $50$ divisions. The spindle advances $1 \mathrm{mm}$ when the screw is given two revolutions. What is the pitch of the screw in centimetre?

The thimble of a screw gauge has $50$ divisions. The spindle advances $1 \mathrm{mm}$ when the screw is given two revolutions. What is the least count of the screw gauge? In the measurement of the diameter of a given wire, the main scale reads $3 \mathrm{mm}$ and $36$ mark on circular scale coincides with the baseline. Find the diameter of the given wire.

In a simple pendulum experiment, draw a graph showing the variation of square of time period with length of the simple pendulum. How will you use this graph to determine the acceleration due to gravity?