# Units and Measurement Test 1

Total Questions:50 Total Time: 60 Min

Remaining:

## Questions 1 of 50

Question:The magnitude of any physical quantity

Depends on the method of measurement

Does not depend on the method of measurement

Is more in SI system than in CGS system

Directly proportional to the fundamental units of mass, length and time

## Questions 2 of 50

Question:Which of the following is not equal to watt

Joule/second

Ampere $$\times$$ volt

(Ampere) $$^{\rm{2}}$$ $$\times$$ohm

Ampere/volt

## Questions 3 of 50

Question:Newtonâ€“second is the unit of

Velocity

Angular momentum

Momentum

Energy

## Questions 4 of 50

Question:A cube has numerically equal volume and surface area. The volume of such a cube is

216 units

1000 units

2000 units

3000 units

## Questions 5 of 50

Question:Wavelength of ray of light is $$0.00006\,m$$. It is equal to

$$6\,\,microns$$

$$60\,\,microns$$

$$600\,\,microns$$

$$0.6\,\,microns$$

## Questions 6 of 50

Question:Electron volt is a unit of

Charge

Potential difference

Momentum

Energy

## Questions 7 of 50

Question:The SI unit of momentum is

$$\frac{{kg}}{m}$$

$$\frac{{kg.m}}{{\sec }}$$

$$\frac{{kg.{m^2}}}{{\sec }}$$

$$kg \times Newton$$

## Questions 8 of 50

Question:The velocity of a particle depends upon as $$v = a + bt + c{t^2}$$; if the velocity is in $$m/\sec$$, the unit of $$a$$ will be

$$m/\sec$$

$$m/{\sec ^2}$$

$${m^2}/\sec$$

$$m/{\sec ^3}$$

## Questions 9 of 50

Question:One million electron volt $$(1\,MeV)$$ is equal to

$${10^5}eV$$

$${10^6}eV$$

$${10^4}eV$$

$${10^7}eV$$

## Questions 10 of 50

Question:If $${u_1}$$ and $${u_2}$$ are the units selected in two systems of measurement and $${n_1}$$ and $${n_2}$$ their numerical values, then

$${n_1}{u_1} = {n_2}{u_2}$$

$${n_1}{u_1} + {n_2}{u_2} = 0$$

$${n_1}{n_2} = {u_1}{u_2}$$

$$({n_1} + {u_1}) = ({n_2} + {u_2})$$

## Questions 11 of 50

Question:$$1\,eV$$ is

Same as one joule

$$1.6 \times {10^{ - 19}}J$$

$$1V$$

$$1.6 \times {10^{ - 19}}C$$

## Questions 12 of 50

Question:$$1kWh =$$

$$1000W$$

$$36 \times {10^5}J$$

$$1000J$$

$$3600\,J$$

## Questions 13 of 50

Question:To determine the Young's modulus of a wire, the formula is $$Y = \frac{F}{A}:\frac{L}{{\Delta L}};$$ where $$L$$ = length, $$A =$$area of cross-section of the wire, $$\Delta L =$$change in length of the wire when stretched with a force $$F$$. The conversion factor to change it from CGS to MKS system is

1

10

0.1

0.01

## Questions 14 of 50

Question:Young's modulus of a material has the same units as

Pressure

Strain

Compressibility

Force

## Questions 15 of 50

Question:One yard in SI units is equal

1.9144 $$metre$$

0.9144 $$metre$$

0.09144 $$kilometre$$

1.0936 $$kilometre$$

## Questions 16 of 50

Question:Dyne/cm2 is not a unit of

Pressure

Stress

Strain

Young's modulus

## Questions 17 of 50

Question:The units of angular momentum are

$$kg - {m^2}/{s^2}$$

$$Joule - s$$

$$Joule/s$$

$$kg - m - {s^2}$$

## Questions 18 of 50

Question:Which of the following is not the unit of energy

Calorie

Joule

Electron volt

Watt

## Questions 19 of 50

Question:Number of base SI units is

4

7

3

5

## Questions 20 of 50

Question:SI unit of permittivity is

$${C^2}{m^2}{N^{ - 1}}$$

$${C^{ - 1}}{m^2}{N^{ - 2}}$$

$${C^2}{m^2}{N^2}$$

$${C^2}{m^{ - 2}}{N^{ - 1}}$$

## Questions 21 of 50

Question:Which does not has the same unit as others

Watt-sec

Kilowatt-hour

eV

J-sec

## Questions 22 of 50

Question:Which pair has the same dimensions

Work and power

Density and relative density

Momentum and impulse

Stress and strain

## Questions 23 of 50

Question:If $$C$$ and $$R$$ represent capacitance and resistance respectively, then the dimensions of $$RC$$ are

$${M^0}{L^0}{T^2}$$

$${M^0}{L^0}T$$

$$M{L^{ - 1}}$$

None of the above

## Questions 24 of 50

Question:Dimensions of one or more pairs are same. Identify the pairs

Torque and work

Angular momentum and work

Energy and Young's modulus

Light  and wavelength

## Questions 25 of 50

Question:Which of the following is dimensionally correct

Pressure = Energy per unit area

Pressure = Energy per unit volume

Pressure = Force per unit volume

Pressure = Momentum per unit volume per unit time

## Questions 26 of 50

Question:Planck's constant has the dimensions (unit) of

Energy

Linear momentum

Work

Angular momentum

## Questions 27 of 50

Question:The equation of state of some gases can be expressed as $$\left( {P + \frac{a}{{{V^2}}}} \right)\,(V - b) = RT$$. Here $$P$$ is the pressure, $$V$$ is the volume, $$T$$ is the absolute temperature and $$a,\,b,\,R$$ are constants. The dimensions of $$'a'$$ are

$$M{L^5}{T^{ - 2}}$$

$$M{L^{ - 1}}{T^{ - 2}}$$

$${M^0}{L^3}{T^0}$$

$${M^0}{L^6}{T^0}$$

## Questions 28 of 50

Question:Dimensional formula of capacitance is

$${c^2}{g^0}{p^{ - 2}}$$

$$M{L^2}{T^4}{A^{ - 2}}$$

$$ML{T^{ - 4}}{A^2}$$

$${M^{ - 1}}{L^{ - 2}}{T^{ - 4}}{A^{ - 2}}$$

## Questions 29 of 50

Question:$$ML{T^{ - 1}}$$ represents the dimensional formula of

Power

Momentum

Force

Couple

## Questions 30 of 50

Question:Dimensional formula of heat energy is

$$M{L^2}{T^{ - 2}}$$

$$ML{T^{ - 1}}$$

$${M^0}{L^0}{T^{ - 2}}$$

None of these

## Questions 31 of 50

Question:The dimensions of physical quantity $$X$$ in the equation Force $$= \frac{X}{{{\rm{Density}}}}$$ is given by

$${M^1}{L^4}{T^{ - 2}}$$

$${M^2}{L^{ - 2}}{T^{ - 1}}$$

$${M^2}{L^{ - 2}}{T^{ - 2}}$$

$${M^1}{L^{ - 2}}{T^{ - 1}}$$

## Questions 32 of 50

Question:The dimensions of $$C{V^2}$$ matches with the dimensions of

$${L^2}I$$

$${L^2}{I^2}$$

$$L{I^2}$$

$$\frac{1}{{LI}}$$

## Questions 33 of 50

Question:The Martians use force $$(F)$$, acceleration  and time $$(T)$$ as their fundamental physical quantities. The dimensions of length on Martians system are

$$F{T^2}$$

$${F^{ - 1}}{T^2}$$

$${F^{ - 1}}{A^2}{T^{ - 1}}$$

$$A{T^2}$$

## Questions 34 of 50

Question:Dimensional formula for torque is

$${L^2}M{T^{ - 2}}$$

$${L^{ - 1}}M{T^{ - 2}}$$

$${L^2}M{T^{ - 3}}$$

$$LM{T^{ - 2}}$$

## Questions 35 of 50

Question:Dimensions of coefficient of viscosity are

$$M{L^2}{T^{ - 2}}$$

$$M{L^2}{T^{ - 1}}$$

$$M{L^{ - 1}}{T^{ - 1}}$$

$$MLT$$

## Questions 36 of 50

Question:The dimension of quantity $$(L/RCV)$$ is

$$[A]$$

$$[{A^2}]$$

$$[{A^{ - 1}}]$$

None of these

## Questions 37 of 50

Question:Dimensions of magnetic field intensity is

$$[{M^0}{L^{ - 1}}{T^0}{A^1}]$$

$$[ML{T^{ - 1}}{A^{ - 1}}]$$

$$[M{L^0}{T^{ - 2}}{A^{ - 1}}]$$

$$[ML{T^{ - 2}}A]$$

## Questions 38 of 50

Question:The force $$F$$ on a sphere of radius $$'a'$$ moving in a medium with velocity $$'v'$$ is given by $$F = 6\pi \eta av$$. The dimensions of $$\eta$$ are

$$M{L^{ - 1}}{T^{ - 1}}$$

$$M{T^{ - 1}}$$

$$ML{T^{ - 2}}$$

$$M{L^{ - 3}}$$

## Questions 39 of 50

Question:Which physical quantities have the same dimension

Couple of force and work

Force and power

Latent heat and specific heat

Work and power

## Questions 40 of 50

Question:Dimensions of luminous flux are

$$M{L^2}{T^{ - 2}}$$

$$M{L^2}{T^{ - 3}}$$

$$M{L^2}{T^{ - 1}}$$

$$ML{T^{ - 2}}$$

## Questions 41 of 50

Question:A physcial quantity $$x$$ depends on quantities $$y$$ and $$z$$ as follows: $$x = Ay + B\tan Cz$$, where $$A,\,B$$ and $$C$$ are constants. Which of the following do not have the same dimensions

$$x$$ and $$B$$

$$C$$ and $${z^{ - 1}}$$

$$y$$ and $$B/A$$

$$x$$ and $$A$$

## Questions 42 of 50

Question:Which of the following pair does not have similar dimensions

Stress and pressure

Angle and strain

Tension and surface tension

Planck's constant and angular momentum

## Questions 43 of 50

Question:Which of the following quantities is dimensionless

Gravitational constant

Planck's constant

Power of a convex lens

None

## Questions 44 of 50

Question:The dimensional formula for Boltzmann's constant is

$$[M{L^2}{T^{ - 2}}{\theta ^{ - 1}}]$$

$$[M{L^2}{T^{ - 2}}]$$

$$[M{L^0}{T^{ - 2}}{\theta ^{ - 1}}]$$

$$[M{L^{ - 2}}{T^{ - 1}}{\theta ^{ - 1}}]$$

## Questions 45 of 50

Question:Position of a body with acceleration 'a' is given by $$x = K{a^m}{t^n},$$here t is time. Find dimension of m and n.

$$m = 1$$, $$n = 1$$

$$m = 1,\;n = 2$$

$$m = 2,\;n = 1$$

$$m = 2,\;n = 2$$

## Questions 46 of 50

Question:Pascal-Second has dimension of

Force

Energy

Pressure

Coefficient of viscosity

## Questions 47 of 50

Question:The unit of percentage error is

Same as that of physical quantity

Different from that of physical quantity

Percentage error is unit less

Errors have got their own units which are different from that of physical quantity measured

## Questions 48 of 50

Question:The decimal equivalent of 1/20 upto three significant figures is

0.05

0.05

0.01

5.0 Ã— 10$$^{ - 2}$$

## Questions 49 of 50

Question:The number of significant figures in all the given numbers 25.12, 2009, 4.156 and $$1.217 \times {10^{ - 4}}$$ is

1

2

3

4

## Questions 50 of 50

Question:If the length of rod A is 3.25 Â± 0.01 cm and that of B is 4.19 Â± 0.01 cm then the rod B is longer than rod A by

0.94 $${\rm{ \pm }}$$ 0.00 cm
0.94 $${\rm{ \pm }}$$ 0.01 cm
0.94 $${\rm{ \pm }}$$ 0.02 cm
0.94 $${\rm{ \pm }}$$ 0.005 cm