Skip to main content
Back to UNITS & MEASUREMENTS

Your Progress

0 / 502 Answered
0
Correct
0
Incorrect
0%
Accuracy
JEE • PHYSICS • UNITS & MEASUREMENTS

Units & measurements practice · Medium

Choose an answer to check it, or open “View answer” to study the explanation. Sign in to save progress to your account.

Practice format and chapter quiz

These sets use single-correct-answer MCQs. They do not cover every JEE Main or JEE Advanced question format and are not full-length mock papers.

Take a chapter quiz →
Showing 421-450 of 502 questions

Preparing practice and saved progress…

421 Medium
421 of 502
Understanding +4 | -1
ML3T−1Q−2M{L^3}{T^{ - 1}}{Q^{ - 2}} is dimensions of
View answer and explanation
Correct option: A
Resistivity
Option A (Resistivity) is correct because the given dimensions match the dimensions of resistivity, derived from the resistance formula.
422 Medium
422 of 502
Analyzing +4 | -1
Which of the following physical quantities have the
same dimensions?
View answer and explanation
Correct option: A
Electric displacement (D→)(\overrightarrow D )
and surface charge
density
Option A is correct because the intensity of sound is related to the energy density of the medium, which increases with the density of the medium.
423 Medium
423 of 502
Analyzing +4 | -1
A physical quantity xx depends on quantities yy and zz as  x=Ay+B   sin⁡    (Cz), \,x = Ay + B\,\,\,\sin \,\,\,\,(Cz),\, where A,  BA,\,\,B and CC are constants. Which of the following have same dimensions?
View answer and explanation
Correct option: D
All of these
Option D (All of these) is correct because, according to the principle of homogeneity, each term in the equation must have the same dimensions, and the argument of a trigonometric function must be dimensionless.
424 Medium
424 of 502
Application +4 | -1
Calculate zz for the following case.
z=(x−2.5y+w)z=(x-2.5 y+w) for x=(4.72±0.12)m,y=(4.4±0.2)m,w=(15.63±0.16)mx=(4.72 \pm0.12) \mathrm{m}, {y}=(4.4 \pm 0.2) \mathrm{m}, {w}=(15.63\pm 0.16) \mathrm{m}.
View answer and explanation
Correct option: C
9.4±0.89.4 \pm 0.8
Option C (9.4±0.89.4 \pm 0.8) is correct because it accurately calculates the value of z and its associated uncertainty based on the given formula and input values.
425 Medium
425 of 502
Analyzing +4 | -1
With the usual notations, the following equation St=u+12a(2t−1)  {S_t} = u + \frac{1}{2}a\left( {2t - 1} \right)\; is
View answer and explanation
Correct option: C
Both numerically and dimensionally correct
Option C is correct. The equation is derived from kinematic equations and is dimensionally consistent, making it both numerically and dimensionally correct.
426 Medium
426 of 502
Understanding +4 | -1
In a metre bridge experiment, we try to obtain the null point at the middle. This:
View answer and explanation
Correct option: A
Reduces systematic error as well as random error
Option A (Reduces systematic error as well as random error) is correct because the sensitivity of the measurement is highest at the middle point.
427 Medium
427 of 502
Application +4 | -1
The dimensions of gravitational constant G and the moment of inertia are respectively
View answer and explanation
Correct option: B
[M−1L3T−2];[ML2T0]\left[ {{\mathrm{M}^{ - 1}}{\mathrm{L}^3}{\mathrm{T}^{ - 2}}} \right];\left[ {\mathrm{M}{\mathrm{L}^2}{\mathrm{T}^0}} \right]
The correct answer is B ([M−1L3T−2{\mathrm{M}^{ - 1}}{\mathrm{L}^3}{\mathrm{T}^{ - 2}}];[ML2T0{\mathrm{M}{\mathrm{L}^2}{\mathrm{T}^0}}]) because it correctly identifies the dimensions of the gravitational constant and moment of inertia.
428 Medium
428 of 502
Analyzing +4 | -1
Assertion: A dimensionless quantity may have unit.

Reason: Two physical quantities having same dimensions, may have different units.
View answer and explanation
Correct option: B
If both assertion and reason are true but reason is not the correct explanation of the assertion
Option B is correct. A dimensionless quantity can have a unit (e.g., radian for angle), and two quantities with the same dimensions can have different units.
429 Medium
429 of 502
Remembering +4 | -1
Dimensional formula for force is
View answer and explanation
Correct option: B
[MLT−2]\left[ {\mathrm{ML}{\mathrm{T}^{ - 2}}} \right]
Option B ([MLT−2\mathrm{ML}{\mathrm{T}^{ - 2}}]) is correct because force is mass times acceleration, and the dimensional formula for mass is [M] and for acceleration is [LT⁻²].
430 Medium
430 of 502
Remembering +4 | -1
The unit of magnetic moment is
View answer and explanation
Correct option: B
JT−1\mathrm{J}{\mathrm{T}^{ - 1}}
Option B (JT−1\mathrm{J}{\mathrm{T}^{ - 1}}) is correct because the unit of magnetic moment is Joule per Tesla (J/T), which is equivalent to Ampere meter squared (A m²).
431 Medium
431 of 502
Remembering +4 | -1
Size of universe is about
View answer and explanation
Correct option: D
10 million light years
Option D (10 million light years) is correct because the observable universe is estimated to be about 10 million light years across.
432 Medium
432 of 502
Application +4 | -1
Which one of the following represents the correct dimensions of the quantity: x=ηρx=\frac{\eta}{\rho}, where
η=\eta= coefficient of viscosity and ρ=\rho= the density of a liquid?
View answer and explanation
Correct option: D
[M0L2T−1]\left[\mathrm{M}^0 \mathrm{L}^2 \mathrm{T}^{-1}\right]
Option D ([M0L2T−1]\left[\mathrm{M}^0 \mathrm{L}^2 \mathrm{T}^{-1}\right]) is correct because the dimensions of viscosity divided by density simplify to L²T⁻¹.
433 Medium
433 of 502
Understanding +4 | -1
The number of significant figures in 0.02300 is
View answer and explanation
Correct option: C
4
Option C (4) is correct because the trailing zeros after the decimal point and after a non-zero digit are significant.
434 Medium
434 of 502
Application +4 | -1
The voltage and current in a conductor are measured as (50±2)V(50 \pm 2) V and (5±0.2)A(5 \pm 0.2) A. The percentage error in the calculation of resistance is
View answer and explanation
Correct option: D
8%8 \%
Option D (88 \\%) is correct because it accurately calculates the percentage error in resistance using the given voltage and current measurements with their respective errors.
435 Medium
435 of 502
Application +4 | -1
The dimensions of emf in MKS is
View answer and explanation
Correct option: D
[ML2T−2Q−1]\left[ {\mathrm{M}{\mathrm{L}^2}{\mathrm{T}^{ - 2}}{\mathrm{Q}^{ - 1}}} \right]
Option D ([ML2T−2Q−1]\left[ {\mathrm{M}{\mathrm{L}^2}{\mathrm{T}^{ - 2}}{\mathrm{Q}^{ - 1}}} \right]) is correct because the dimensions of emf are derived from its definition in terms of inductance and current.
436 Medium
436 of 502
Application +4 | -1
Let us choose a new unit of length such that the velocity of light in vacuum is unity. If light takes 8 min and 20 sec to cover the distance between sun and earth, this distance in terms of the new unit is
View answer and explanation
Correct option: C
500
Option C (500) is correct because the distance is the product of the speed of light (unity) and the time taken in the new unit.
437 Medium
437 of 502
Application +4 | -1
Volume of liquid flowing per second through a capillary tube is given by V=K[x2−x1]4[y2−y1]\mathrm{V}=\frac{\mathrm{K}\left[\mathrm{x}_2-\mathrm{x}_1\right]^4}{\left[\mathrm{y}_2-\mathrm{y}_1\right]} where x1x_1 and x2x_2 are inner and outer radii and y2y_2 and y1y_1 are positions crossed by the liquid. The dimensional formula for K\mathrm{K} is :-
View answer and explanation
Correct option: D
M0 L0 T−1\mathrm{M}^0 \mathrm{~L}^0 \mathrm{~T}^{-1}
Option D (M0L0T−1\mathrm{M}^0 \mathrm{L}^0 \mathrm{T}^{-1}) is correct because it is derived from the dimensional analysis of the given equation for the volume flow rate.
438 Medium
438 of 502
Understanding +4 | -1
How many wavelengths of Kr86  K{r^{86}}\mathrm{\;} are there in one metre
View answer and explanation
Correct option: B
1650763.73
Option B (1650763.73) is correct because this is the defined number of wavelengths of Kr86K{r^{86}} in one meter according to the historical definition of the meter.
439 Medium
439 of 502
Understanding +4 | -1
The number of significant figures in all the given number 25.12, 2022, 4.389, and 1.812×10−61.812 \times {10^{ - 6}} is
View answer and explanation
Correct option: D
4
Option D (4) is correct because each of the given numbers has four significant figures.
440 Medium
440 of 502
Remembering +4 | -1
If the digit to be dropped is more than 5, then the preceding digit is _____.
View answer and explanation
Correct option: A
Raised by 1
Option A (Raised by 1) is correct because that's the rounding rule when the digit to be dropped is greater than 5.
441 Medium
441 of 502
Remembering +4 | -1
One shake is equal to
View answer and explanation
Correct option: B
10−810^{-8} seconds
Option B (10−810^{-8} seconds) is correct because one shake is defined as 10−810^{-8} seconds.
442 Medium
442 of 502
Analyzing +4 | -1
Statement I: The dimensional method cannot be used to obtain the dependence of the work done by a force FF on the angle θ\theta between force FF and displacement xx.

Statement II: Angle can be measured in radians but it has no dimensions.
View answer and explanation
Correct option: A
Statement I is true, Statement II is true; Statement II is the correct explanation for Statement I
Option A is correct because Statement I is true, Statement II is true, and Statement II is the correct explanation for Statement I. Dimensional analysis cannot determine the dependence on dimensionless quantities like angles.
443 Medium
443 of 502
Remembering +4 | -1
The dimension of torque is
View answer and explanation
Correct option: A
[ML2T−2]\left[M L^2 T^{-2}\right]
Option A ([M L² T⁻²]) is correct because torque is force times distance, and the dimensions of force are [M L T⁻²] and distance is [L], so torque is [M L² T⁻²].
444 Medium
444 of 502
Understanding +4 | -1
Which of the following pairs has the dimensions of length?
View answer and explanation
Correct option: A
Radius of gyration and light year
Option A (Radius of gyration and light year) is correct because both radius of gyration and light year have the dimension of length.
445 Medium
445 of 502
Understanding +4 | -1
Dimensions of coefficient of viscosity are
View answer and explanation
Correct option: C
ML−1T−1M{L^{ - 1}}{T^{ - 1}}
The correct answer is C (ML−1T−1M{L^{ - 1}}{T^{ - 1}}) because the coefficient of viscosity is defined by the formula F = -ηA(dv/dx), and solving for η gives the stated dimensions.
446 Medium
446 of 502
Understanding +4 | -1
The dimensions [ML2T−2A−1]\left[\mathrm{ML}^2 \mathrm{T}^{-2} \mathrm{A}^{-1}\right] belong to the:
View answer and explanation
Correct option: D
Magnetic flux
The correct answer is Magnetic flux because its dimensions are equivalent to inductance multiplied by current, which matches the given dimensions.
447 Medium
447 of 502
Application +4 | -1
The ratio of S.I unit of universal gravitational constant to C.G.S unit is
View answer and explanation
Correct option: A
103{10^3}
Option A (103{10^3}) is correct because the ratio of the SI unit to the CGS unit of the universal gravitational constant is calculated using dimensional analysis.
448 Medium
448 of 502
Analyzing +4 | -1
Farad is not equivalent to
View answer and explanation
Correct option: B
qv2q{v^2}
Option B (qv2q{v^2}) is correct because Farad is the unit of capacitance, which is equivalent to qV\frac{q}{V}, q2J\frac{{{q^2}}}{J}, and JV2\frac{J}{{{V^2}}}, but not qv2q{v^2}.
449 Medium
449 of 502
Application +4 | -1
The potential energy of a particle that varies with distance x{x} is V(x)=−αx+βsin⁡xγ{V}(x)=-\alpha x+\beta \sin \frac{x}{\gamma}. A dimensionless combination of constants α,β,γ\alpha, \beta, \gamma is
View answer and explanation
Correct option: D
αγβ\frac{\alpha \gamma}{\beta}
The correct answer is αγβ\frac{\alpha \gamma}{\beta} because the dimensions of each term in the potential energy equation must be the same, allowing us to find a dimensionless combination.
450 Medium
450 of 502
Remembering +4 | -1
Dimensional formula of heat energy is
View answer and explanation
Correct option: A
ML2T−2M{L^2}{T^{ - 2}}
Option A (ML2T−2M{L^2}{T^{ - 2}}) is correct because heat energy, like all forms of energy, has the dimensions of mass times length squared divided by time squared.
Revision notes and key takeaways

Review UNITS & MEASUREMENTS in your textbook or class notes, then use this set to check your understanding.

Showing 421-450 of 502 questions

Your practice

0 / 502 answered · 502 remaining · 0% accuracy

Progress is stored on this device. Sign in to save to your account.

✓ Correct · ✗ Incorrect · ○ Unanswered

Answer feedback and difficulty

Type at least 2 characters or jump directly:
🔓

Save your learning progress

Sign in with a free account to save your practice answers and quiz results, then return to them when you revise.