G L Mittal and TARUN MITTAL Solutions for Chapter: Significant Figures, Exercise 3: FOR DIFFERENT COMPETITIVE EXAMINATIONS

The respective number of significant figures for the number $23.023, 0.003 \mathrm{and} 2.1\times {10}^{-3}$ are:

The order of magnitude of $({10}^7+{10}^2)$ is

The order of magnitude of human life is: (in seconds)

The pitch of a screw gauge is $0.5 \mathrm{mm}$ and its head scale has $50$ divisions. The least count of the screw gauge is:

A spherometer has a least count of $0.005 \mathrm{mm}$ and its head scale is divided into $200$ equal divisions. The distance between consecutive thread on the spherometer screw is:

The vernier of the circular scale of a spectrometer has $30$ divisions which coincide against $29$ divisions of the main scale. The value of a main scale division is $0.5°$. The least count of the spectrometer is:

The time taken by a radio wave to go and come back after reflection from a communication satellite is:

A body of mass $\mathrm{m}=3.513 \mathrm{Kg}$ is moving along the X-axis with a speed of $5.00 {\mathrm{ms}}^{-1}$. The magnitude of its momentum is recorded as: