NCERT Solutions for Chapter: Units and Measurement, Exercise 1: MCQ-I

The numbers $2.745$ and $2.735$ on rounding off to $3$ significant figures will give.

Which of the following pairs of physical quantities does not have same dimensional formula?

Measure of two quantities along with the precision of respective measuring instrument is$A=2.5 \mathrm{m} {\mathrm{s}}^{-1}\pm 0.5 \mathrm{m} {\mathrm{s}}^{-1}$ and $\mathrm{B}=0.10 \mathrm{s}\pm 0.01 \mathrm{s}$.

Find the value of $\mathrm{AB}$ will be

You measures two quantities as $A=(1.0\pm 0.2)m,B=2.0\mathrm{m}\pm 0.2\mathrm{m}$. we report correct value of $\sqrt{AB}$ as:

Which of the following measurement is most precise?

The mean length of an object is $5\mathrm{cm}$. Which of the following measurement is most accurate?

Young's modulus of steel is $1.9\times {10}^{11}\mathrm{N}/{\mathrm{m}}^2$. When expressed in CGS units of $dyne/c{m}^2$. It will be equal to$\left(1N={10}^5 dynes, and 1 m^2={10}^4 c{m}^2\right)$.

If the momentum $\left(P\right)$, area $\left(A\right)$ and time $\left(T\right)$ are taken to be fundamental quantities, then energy has dimensional formula.