# MCQs for Physics Class 11 with Answers Chapter 2 Units and Measurements

Students of class 11 Physics should refer to MCQ Questions Class 11 Physics Units and Measurements with answers provided here which is an important chapter in Class 11 Physics NCERT textbook. These MCQ for Class 11 Physics with Answers have been prepared based on the latest CBSE and NCERT syllabus and examination guidelines for Class 11 Physics. The following MCQs can help you to practice and get better marks in the upcoming class 11 Physics examination

## Chapter 2 Units and Measurements MCQ with Answers Class 11 Physics

MCQ Questions Class 11 Physics Units and Measurements provided below have been prepared by expert teachers of grade 11. These objective questions with solutions are expected to come in the upcoming Standard 11 examinations. Learn the below provided MCQ questions to get better marks in examinations.

Question. Temperature can be expressed as derived quantity in terms of
(a) length and mass
(b) mass and time
(c) length, mass and time
(d) None of these

D

Question. Illuminance of a surface is measured in
(a) Lumen
(b) candela
(c) lux
(d) lux m–2

C

Question. What is the unit of “a” in Vander Waal’s gas equation?
(a) Atm litre–2 mol2
(b) Atm litre2 per mol
(c) Atm litre–1 mol2
(d) Atm litre2 mol–2

B

Question. SI unit of electric polarisation is
(a) Cm–2
(b) coulomb
(c) ampere
(d) volt

A

Question. If f = x2, then the relative error in f is

A

Question. Which is dimensionless?
(a) Force/acceleration
(b) Velocity/acceleration
(c) Volume/area
(d) Energy/work

D

Question. Random error can be eliminated by
(a) careful observation
(b) eliminating the cause
(c) measuring the quantity with more than one instrument
(d) taking large number of observations and then their mean

D

Question. Two quantities A and B have different dimensions which mathematical operation given below is physically meaningful?
(a) A/B
(b) A + B
(c) A – B
(d) A = B

A

Question. Which of the following systems of units is not based on units of mass, length and time alone
(a) SI
(b) MKS
(b) CGS
(d) FPS

A

Question. The physical quantity which has the dimensional formula [M1T–3] is
(a) surface tension
(b) solar constant
(c) density
(d) compressibility

B

Question. The SI unit of pressure is
(a) atmosphere
(b) bar
(c) pascal
(d) mm of Hg

C

Question. The SI unit of coefficient of mutual inductance of a coil is
(a) henry
(b) volt
(c) weber

A

Question. Light year is
(a) light emitted by the sun in one year.
(b) time taken by light to travel from sun to earth.
(c) the distance travelled by light in free space in one year.
(d) time taken by earth to go once around the sun.

C

Question. The S.I. unit of pole strength is
(a) Am2
(b) Am
(c) A m–1
(d) Am–2

B

Question. The dimensional formula for entropy is
(a) [MLT–2 K1]
(b) [ML2 T–2]
(c) [ML2 T–2 K–1]
(d) [ML2 T–2 K]

C

Question. The dimensional formula of current density is
(a) [M0L-2T-1Q]
(b) [M0L2T1Q-1]
(c) [MLT-1Q]
(d) [ML-2T-1Q2 ]

A

Question. If e is the charge, V the potential difference, T the temperature, then the units of eV/T are the same as that of
(a) Planck’s constant
(b) Stefan’s constant
(c) Boltzmann constant
(d) gravitational constant

C

Question. Potential is measured in
(a) joule/coulomb
(b) watt/coulomb
(c) newton-second
(d) None of these

A

Question. Maxwell is the unit of
(a) magnetic susceptibility
(b) intensity of Magnetisation
(c) magnetic Flux
(d) magnetic Permeability

C

Question. Which physical quantities have same dimensions?
(a) Moment of couple and work
(b) Force and power
(c) Latent heat and specific heat
(d) Work and power

A

Question. What are the units of magnetic permeability?
(a) Wb A–1 m–1
(b) Wb–1 Am
(c) Wb A m–1
(d) Wb A–1 m

A

Question. The dimensions of universal gas constant are
(a) [L2 M1 T–2 K–1]
(b) [L1 M2 T–2 K–1]
(c) [L1 M1 T–2 K–1]
(d) [L2 M2 T–2 K–1]

A

Question. The dimensions of Wien’s constant are
(a) [ML0 T K]
(b) [M0 LT0 K]
(c) [M0 L0 T K]
(d) [MLTK]

B

Question. The period of a body under S.H.M. is represented by: T = Pa Db Sc where P is pressure, D is density and S is surface tension, then values of a, b and c are

A

Question. The unit and dimensions of impedance in terms of charge Q are
(a) mho, [ML2 T–2 Q–2]
(b) ohm, [ML2 T–1 Q–2]
(c) ohm, [ML2 T–2 Q–1]
(d) ohm, [MLT–1 Q–1]

B

Question. If L denotes the inductance of an inductor through which a current i is flowing, the dimensions of L i2 are
(a) [ML2 T–2]
(b) [MLT–2]
(c) [M2 L2 T–2]
(d) Not expressible in M, L, T

A

Question. The dimensional formula of wave number is
(a) [M0 L0 T–1]
(b) [M0 L–1 T0]
(c) [M–1 L–1 T0]
(d) [M0 L0 T0]

B

Question. The time of oscillation T of a small drop of liquid depends on radius r, density r and surface tension S. The relation between them is given by

B

Question. Distance travelled by a particle at any instant ‘t’ can be represented as S = A (t + B) + Ct2. The dimensions of B are
(a) [M0 L1T-1]
(b) [M0 L0 T1]
(c) [M0 L-1T-2 ]
(d) [M0 L2 T-2]

B

Question. If C and L denote the capacitance and inductance, the dimensions of LC are
(a) [M0 L0 T–1]
(b) [M0 L–1 T0]
(c) [M–1 L–1 T0]
(d) [M0 L0 T2]

D

Question. The deBroglie wavelength associated with a particle of mass m and energy E is h /√2mE . The dimensional formula of Planck’s constant h is
(a) [M2 L2 T-2 ]
(b) [ML2 T-1]
(c) [MLT-2 ]
(d) [ML2 T-2 ]

B

Question. The dimensions of Hubble’s constant are
(a) [T-1]
(b) [M0L0T2 ]
(c) [MLT4 ]
(d) [MT-1 ]

A

Question. Subtract 0.2 J from 7.26 J and express the result with correct number of significant figures.
(a) 7.1 J
(b) 7.06 J
(c) 7.0 J
(d) 7 J

A

Question. Relative density of a metal may be found with the help of spring balance. In air the spring balance reads (5.00 ± 0.05) N and in water it reads (4.00 ± 0.05) N. Relative density would be
(a) (5.00 ± 0.05)N
(b) (5.00 ± 11%)
(c) (5.00 ± 0.10)
(d) (5.00 ± 6%)

D

Question. The potential energy of a particle varies with distance x from a fixed origin as V = (A√x/x+B) where A and B are constants. The dimensions of AB are
(a) [M1L5/ 2 T-2 ]
(b) [M1L2 T-2 ]
(c) [M3/ 2 L5/ 2 T-2 ]
(d) [M1L7 / 2 T-2 ]

D

Question. Area of a square is (100 ± 2) m2. Its side is
(a) (10 ± 1) m
(b) (10 ± 0.1) m
(c) (10 ± √2)m
(d) 10 ± √2%

A

Question. If L and R denote inductance and resistance then dimension of L/R is
(a) [M0L0T0 ]
(b) [M0L0T]
(c) [M2L0T2 ]
(d) [MLT2 ]

B

Question. The least count of a stop watch is 0.2 second. The time of 20 oscillations of a pendulum is measured to be 25 second. The percentage error in the measurement of time will be
(a) 8%
(b) 1.8%
(c) 0.8%
(d) 0.1%

C

Question. The dimensions of solar constant is
(a) [M0 L0 T0]
(b) [MLT–2]
(c) [ML2 T–2]
(d) MT–3

D

Question. The expression [ML–1 T–2] does not represent
(a) pressure
(b) power
(c) stress
(d) Young’s modulus

B

Question. Dimensions of specific heat are
(a) [ML2 T–2 K]
(b) [ML2 T–2 K–1]
(c) [ML2 T2 K–1]
(d) [L2 T–2 K–1]

D

Question. Electron volt is a unit of
(a) potential difference
(b) charge
(c) energy
(d) capacity

C

Question. Which of the following is the most accurate?
(a) 200.0 m
(b) 20 × 101 m
(c) 2 × 102 m

A

Question. The velocity of water waves (v) may depend on their wavelength λ, the density of water r and the acceleration due to gravity, g. The method of dimensions gives the relation between these quantities is
(a) v
(b) v2 ∝ g λ
(c) v2 ∝ g λ2
(d) v2 ∝ g-1 λ2

B

Question. The time dependence of a physical quantity p is given by p = p0 exp. (– a t2), where a is a constant and t is the time. The constant a
(a) is dimensionless
(b) has dimensions T–2
(c) has dimensions T2
(d) has dimensions of p.

B

Question. Dimensions of ‘ohm’ are same as (where h is Planck’s constant and e is charge)
(a) h/e
(b) h2/e
(c) h/e2
(d) h2/e2

C

Question. L, C, R represent physical quantities inductance, capacitance and resistance respectively. The combinations which have the dimensions of frequency are
(a) 1/RC
(b) R/L
(c) 1/√LC
(d) C/L

C

Question. A quantity is represented by X = Ma Lb Tc. The % error in measurement of M, L and T are a%, b% and g% respectively. The % error in X would be
(a) (αa +βb + g c)%
(b) (αa -βb + g c)%
(c) (αa -βb – g c)´100%
(d) None of these

A

Question. Using mass (M), length (L), time (T) and electric current (A) as fundamental quantities the dimensions of permittivity will be
(a) [MLT–1A–1]
(b) [MLT–2A–2]
(c) [M–1L–3T+4A2]
(d) [M2L–2T–2A2]

C

Question. The dimensional formula of farad is
(a) [M-1L-2TQ]
(b) [M-1L-2T2Q2 ]
(c) [M-1L-2TQ2 ]
(d) [M-1L-2T2Q]

B

Question. A spherical body of mass m and radius r is allowed to fall in a medium of viscosity h. The time in which the velocity of the body increases from zero to 0.63 times the terminal velocity (v) is called time constant t. Dimensionally t can be represented by

D

Question. The percentage errors in the measurement of mass and speed are 2% and 3% respectively. The error, in kinetic energy obtained by measuring mass and speed, will be
(a) 12 %
(b) 10 %
(c) 8 %
(d) 2 %

C

Question. In a Vernier calliper, N divisions of vernier scale coincide with (N–1) divisions of main scale (in which one division represents 1 mm). the least count of the instrument in cm. should be
(a) N
(b) N – 1
(c) 1 / – 10 N
(d) 1 / N – 1

C

Question. What is the fractional error in g calculated from T = 2p √l / g ? Given fraction errors in T and l are ± x and ± y respectively.
(a) x + y
(b) x – y
(c) 2x + y
(d) 2x – y

C

Question. Conversion of 1 MW power in a New system of units having basic units of mass, length and time as 10 kg, 1 dm and 1 minute respectively is
(a) 2.16 × 1010 unit
(b) 2 × 104 unit
(c) 2.16 × 1012 unit
(d) 1.26 × 1012 unit

C

Question. A resistor of 10 k Ω having tolerance 10% is connected in series with another resistor of 20 k Ω having tolerance 20%. The tolerance of the combination will be
(a) 10%
(b) 13%
(c) 30%
(d) 20%

C

Question. The speed of sound in a gas is given by v = √γRT/M
R = universal gas constant,
T = temperature
M = molar mass of gas
The dimensional formula of g is
(a) [M0L0T0 ]
(b) [M0LT-1]
(c) [MLT-2 ]
(d) [M0L0T-1]

A

Question. Given that r = m2 sin pt , where t represents time. If the unit of m is N, then the unit of r is
(a) N
(b) N2
(c) Ns
(d) N2s