If the length of rod A is $\left( {3.25\; \pm 0.01} \right)\;{\rm{cm}}$ and that of B is $\left( {4.19\; \pm 0.01} \right){\rm{\;cm}},$, then the rod B is longer than rod A by

$\left( {0.94{\rm{\;}} \pm 0.02} \right){\rm{\;cm}}$

$\left( {0.94{\rm{\;}} \pm 0.00} \right){\rm{\;cm}}$

$\left( {0.94{\rm{\;}} \pm 0.01} \right){\rm{\;cm}}$

$\left( {0.94{\rm{\;}} \pm 0.005} \right){\rm{\;cm}}$

Back to UNITS & MEASUREMENTS

Your Progress

0 / 616 Answered

Correct

Incorrect

Accuracy

JEE • PHYSICS • UNITS & MEASUREMENTS

Units & measurements practice · Mixed difficulty

Try a question, then open “View answer” to check it. Sign in to submit answers and save progress.

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 601-616 of 616 questions

601 Medium

601 of 616

Application +4 | -1

A stone weighs

(10.0 \pm 0.1) \mathrm{kg}

in air. The weight of the stone in water is

(5.0 \pm 0.1) \mathrm{kg}

. Find the maximum percentage error in the measurement of specific gravity.

View answer and explanation

Correct option: A

5 \%

Option A (

5 \%

) is correct because the maximum percentage error in specific gravity is calculated by adding the percentage errors in weight in air and loss of weight in water.

602 Medium

602 of 616

Application +4 | -1

A screw gauge of pitch

0.5 \mathrm{~mm}

is used to measure the diameter of uniform wire of length

6.8 \mathrm{~cm}

, the main scale reading is

1.5 \mathrm{~mm}

and circular scale reading is 7 . The calculated curved surface area of wire to appropriate significant figures is :
[Screw gauge has 50 divisions on its circular scale]

View answer and explanation

Correct option: B

3.4 \mathrm{~cm}^2

Option B (

3.4 \mathrm{~cm}^2

) is correct because it calculates the diameter using the screw gauge readings and then calculates the curved surface area of the wire.

603 Medium

603 of 616

Application +4 | -1

If the units of

M, L

are doubled then the unit of kinetic energy will become:

View answer and explanation

Correct option: D

8 times

Option D (8 times) is correct because the kinetic energy is proportional to mass and the square of length, so doubling both results in an 8-fold increase.

604 Easy

604 of 616

Understanding +4 | -1

Henry/ohm can be expressed in

View answer and explanation

Correct option: A

Second

Option A is correct because the ratio of inductance (Henry) to resistance (Ohm) has the dimensions of time (seconds).

605 Easy

605 of 616

Understanding +4 | -1

Assertion : Specific gravity of a fluid is a dimensionless quantity.

Reason : It is the ratio of density of fluid to the density of water.

View answer and explanation

Correct option: A

If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

The correct answer is A (If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion) because specific gravity is a dimensionless ratio of densities.

606 Medium

606 of 616

Remembering +4 | -1

The ratio between pico and giga is

View answer and explanation

Correct option: B

10^{-21}

Option B (

10^{-21}

) is correct because pico is

10^{-12}

and giga is

10^9

, so the ratio is

10^{-12} / 10^9 = 10^{-21}

607 Medium

607 of 616

Application +4 | -1

In SI units, the dimensions of

\sqrt {\frac{{{ \in _0}}}{{{\mu _0}}}}

View answer and explanation

Correct option: D

A{}^2{T^3}{M^{ - 1}}{L^{ - 2}}

The correct answer is D (

A{}^2{T^3}{M^{ - 1}}{L^{ - 2}}

) because it correctly represents the dimensions of the given expression in SI units.

608 Easy

608 of 616

Understanding +4 | -1

The dimensions of shear modulus are

View answer and explanation

Correct option: C

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

Option C is correct because shear modulus is defined as stress/strain, and its dimensions are

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

609 Medium

609 of 616

Analyzing +4 | -1

Which of the following sets have different dimensions?

View answer and explanation

Correct option: D

Dipole moment, Electric flux, Electric field

Option D (Dipole moment, Electric flux, Electric field) is correct because these quantities have different dimensions, unlike the other options where the quantities have the same dimensions.

610 Medium

610 of 616

Application +4 | -1

If the length of rod A is

\left( {3.25\; \pm 0.01} \right)\;\mathrm{cm}

and that of B is

\left( {4.19\; \pm 0.01} \right)\mathrm{\;cm},

, then the rod B is longer than rod A by

View answer and explanation

Correct option: C

\left( {0.94\mathrm{\;} \pm 0.02} \right)\mathrm{\;cm}

Option C

\left( {0.94\mathrm{\;} \pm 0.02} \right)\mathrm{\;cm}

is correct because the difference in lengths is calculated by subtracting the lengths and adding the uncertainties.

611 Medium

611 of 616

Analyzing +4 | -1

From the dimensional consideration, which of the following equation is correct

View answer and explanation

Correct option: A

T = 2\pi r\sqrt {\begin{array}{cccccccccccccccccccc} {\frac{{{R^3}}}{{GM}}}\\ \; \end{array}}

Option A (

T = 2\pi r\sqrt {\begin{array}{cccccccccccccccccccc}{\frac{{{R^3}}}{{GM}}}\\;\end{array}}

) is correct because dimensional analysis confirms that the dimensions on both sides of the equation match.

612 Medium

612 of 616

Understanding +4 | -1

Assertion: The number 1.202 has four significant figures and the number 0.0024 has two significant figures.
Reason: All the non-zero digits are significant.

View answer and explanation

Correct option: B

If both assertion and reason are true but reason is not the correct explanation of assertion

Option B (If both assertion and reason are true but reason is not the correct explanation of assertion) is correct because both statements are true, but the reason does not fully explain the assertion as embedded zeros are also significant.

613 Medium

613 of 616

Application +4 | -1

x = at + \frac{1}{2}b{t^2}

, where ‘x’ is in metre and ‘t’ in second. Then unit of ‘b’ is?

View answer and explanation

Correct option: D

m{s^{ - 2}}

Option D (

m{s^{ - 2}}

) is correct because the unit of 'b' is determined by dimensional analysis, ensuring the equation is dimensionally consistent.

614 Medium

614 of 616

Understanding +4 | -1

Given below are two statement :

Statements I : Astronomical unit (Au), Parsec (Pc) and Light year (ly) are units for measuring astronomical distances.

Statements II : Au < Parsec (Pc) < ly

In the light of the above statements, choose the most appropriate answer from the options given below:

View answer and explanation

Correct option: B

Statements I is correct but Statements II is
incorrect

Option B is correct because Astronomical Unit (AU), Parsec (Pc), and Light Year (ly) are indeed units for measuring astronomical distances, but the correct order is AU < ly < Parsec.

615 Easy

615 of 616

Understanding +4 | -1

Zero error in an instrument is a

View answer and explanation

Correct option: B

Systematic error

Option B (Systematic error) is correct because zero error is a consistent error associated with the instrument itself.

Explore Other Chapters in PHYSICS

View All →

WAVES 566 MCQs THERMAL PROPERTIES OF MATTER 564 MCQs WORK-ENERGY-POWER 553 MCQs MOTION IN PLANE 530 MCQs OSCILLATIONS 498 MCQs SYSTEM OF PARTICLES 498 MCQs

616 Medium

616 of 616

Application +4 | -1

A force ‘F’ is applied onto a square plate of side L. If the percentage error in determining L is 2% and that in F is 4%, then the percentage error in pressure is

View answer and explanation

Correct option: D

0.08

Option D (8%) is correct because the percentage error in pressure is the sum of the percentage error in force and twice the percentage error in length.

Revision notes and key takeaways

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

Showing 601-616 of 616 questions

Continue Your Practice

📚 Switch Set (ALL)

Chapter Sets

ALL 616 MCQs EASY 99 MCQs HARD 15 MCQs MEDIUM 502 MCQs

0 /616

0✓ 0✗

0% Accuracy