## Units and Measurement Questions and Answers Part-2

1. SI unit of pressure is
a) Pascal
b) $Dynes\diagup cm ^{2}$
c) cm of Hg
d) Atmosphere

Explanation: SI unit of pressure is Pascal

2. The unit of angular acceleration in the SI system is
a) N K $g ^{-1}$
b) $m s ^{-2}$
c) rad $s ^{-2}$
d) m $K g ^{-1}K$

Explanation:

3. The unit of Stefan's constant $\sigma$ is
a) $W m ^{-2}K ^{-1}$
b) $W m ^{2}K ^{-4}$
c) $W m ^{-2}K ^{-4}$
d) $W m ^{-2}K ^{4}$

Explanation:

4. Which of the following is not a unit of energy
a) $W-s$
b) $kg-m \diagup sec$
c) $N-m$
d) Joule

Explanation: Kg-m/sec is the unit of linear momentum

5. In $S=a+bt+ct^{2}$  . S is measured in metres and t in seconds. The unit of c is
a) None
b) m
c) $ms^{-1}$
d) $ms^{-2}$

Explanation: ct2 must have dimensions of L
c must have dimensions of L/T2 i.e. LT-2

6. Joule-second is the unit of
a) Work
b) Momentum
c) Pressure
d) Angular momentum

Explanation:

i.e. the unit of angular momentum is joule-second.

7. Unit of energy in SI system is
a) Erg
b) Calorie
c) Joule
d) Electron volt

Explanation: Unit of energy in SI system is Joule

8. A cube has numerically equal volume and surface area. The volume of such a cube is
a) 216 units
b) 1000 units
c) 2000 units
d) 3000 units

Explanation:

9. Wavelength of ray of light is 0.00006 m . It is equal to
a) 6 microns
b) 60 microns
c) 600 microns
d) 0.6 microns