# Units and Measurement Test 1

Total Questions:50 Total Time: 60 Min

Remaining:

## Questions 1 of 50

Question:The magnitude of any physical quantity

### Answers Choices:

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

### Answers Choices:

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

### Answers Choices:

$$6\,\,microns$$

$$60\,\,microns$$

$$600\,\,microns$$

$$0.6\,\,microns$$

## Questions 6 of 50

Question:Electron volt is a unit of

### Answers Choices:

Charge

Potential difference

Momentum

Energy

## Questions 7 of 50

Question:The SI unit of momentum is

### Answers Choices:

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

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

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

$$kg \times Newton$$

## 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

### Answers Choices:

$$m/\sec$$

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

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

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

## Questions 9 of 50

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

### Answers Choices:

$${10^5}eV$$

$${10^6}eV$$

$${10^4}eV$$

$${10^7}eV$$

## 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

### Answers Choices:

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

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

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

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

## Questions 11 of 50

Question:$$1\,eV$$ is

### Answers Choices:

Same as one joule

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

$$1V$$

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

## Questions 12 of 50

Question:$$1kWh =$$

### Answers Choices:

$$1000W$$

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

$$1000J$$

$$3600\,J$$

## 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

### Answers Choices:

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

### Answers Choices:

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

$$Joule - s$$

$$Joule/s$$

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

## 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

### Answers Choices:

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

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

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

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

## 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

### Answers Choices:

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

### Answers Choices:

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

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

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

None of the above

## Questions 24 of 50

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

### Answers Choices:

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

### Answers Choices:

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

### Answers Choices:

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

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

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

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

## Questions 28 of 50

Question:Dimensional formula of capacitance is

### Answers Choices:

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

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

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

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

## 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

### Answers Choices:

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

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

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

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

### Answers Choices:

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

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

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

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

## Questions 32 of 50

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

### Answers Choices:

$${L^2}I$$

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

$$L{I^2}$$

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

## 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

### Answers Choices:

$$F{T^2}$$

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

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

$$A{T^2}$$

## Questions 34 of 50

Question:Dimensional formula for torque is

### Answers Choices:

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

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

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

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

## Questions 35 of 50

Question:Dimensions of coefficient of viscosity are

### Answers Choices:

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

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

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

$$MLT$$

## Questions 36 of 50

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

### Answers Choices:

$$[A]$$

$$[{A^2}]$$

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

None of these

## Questions 37 of 50

Question:Dimensions of magnetic field intensity is

### Answers Choices:

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

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

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

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

## 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

### Answers Choices:

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

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

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

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

## Questions 39 of 50

Question:Which physical quantities have the same dimension

### Answers Choices:

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

### Answers Choices:

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

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

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

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

## 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

### Answers Choices:

$$x$$ 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

### Answers Choices:

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

### Answers Choices:

Gravitational constant

Planck's constant

Power of a convex lens

None

## Questions 44 of 50

Question:The dimensional formula for Boltzmann's constant is

### Answers Choices:

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

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

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

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

## 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.

### Answers Choices:

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

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

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

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

## Questions 46 of 50

Question:Pascal-Second has dimension of

### Answers Choices:

Force

Energy

Pressure

Coefficient of viscosity

## Questions 47 of 50

Question:The unit of percentage error is

### Answers Choices:

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

### Answers Choices:

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

### Answers Choices:

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