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

Answer: a
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 \[K g ^{-1}K\]

Answer: c

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) \[W m ^{-2}K ^{4}\]

Answer: c

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

Answer: b
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) \[ms^{-2}\]

Answer: d
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

Answer: d
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

Answer: c
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

Answer: a

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

Answer: b
Explanation: 6 * 10-5 = 60 * 10-6 = 60 microns

10. Electron volt is a unit of
a) Charge
b) Potential difference
c) Momentum
d) Energy

Answer: d
Explanation: Electron volt is a unit of Energy