JEE Advanced
2025
MCQ
A temperature difference can generate e.m.f. in some materials. Let S be the e.m.f. produced per unit temperature difference between the ends of a wire, σ the electrical conductivity and κ the thermal conductivity of the material of the wire. Taking M, L, T, I and K as dimensions of mass, length, time, current and temperature, respectively, the dimensional formula of the quantity $Z = \frac{S^2 \sigma}{\kappa}$ is :
JEE Advanced
2025
MCQ
Figure 1 shows the configuration of main scale and Vernier scale before measurement. Fig. 2 shows the configuration corresponding to the measurement of diameter D of a tube. The measured value of D is:
JEE Advanced
2025
MCQ
Length, breadth and thickness of a strip having a uniform cross section are measured to be 10.5 cm, 0.05 mm, and 6.0 μm, respectively. Which of the following option(s) give(s) the volume of the strip in cm3 with correct significant figures:
JEE Advanced
2024
MCQ
A dimensionless quantity is constructed in terms of electronic charge $e$, permittivity of free space $\varepsilon_0$, Planck's constant $h$, and speed of light $c$. If the dimensionless quantity is written as $e^\alpha \varepsilon_0{ }^\beta h^\gamma c^\delta$ and $n$ is a non-zero integer, then $(\alpha, \beta, \gamma, \delta)$ is given by :
JEE Advanced
2023
MCQ
Young's modulus of elasticity $Y$ is expressed in terms of three derived quantities, namely, the gravitational constant $G$, Planck's constant $h$ and the speed of light $c$, as $Y=c^\alpha h^\beta G^\gamma$. Which of the following is the correct option?
JEE Advanced
2022
MCQ
Area of the cross-section of a wire is measured using a screw gauge. The pitch of the main scale is $0.5 \mathrm{~mm}$. The circular scale has 100 divisions and for one full rotation of the circular scale, the main scale shifts by two divisions. The measured readings are listed below.
| Measurement condition |
Main scale reading |
Circular scale reading |
Two arms of gauge touching each other without wire |
0 division |
4 divisions |
| Attempt-1: With wire |
4 divisions |
20 divisions |
| Attempt-2: With wire |
4 divisions |
16 divisions |
What are the diameter and cross-sectional area of the wire measured using the screw gauge?
JEE Advanced
2021
MCQ
The smallest division on the main scale of a Vernier calipers is 0.1 cm. Ten divisions of the Vernier scale correspond to nine divisions of the main scale. The figure below on the left shows the reading of this calipers with no gap between its two jaws. The figure on the right shows the reading with a solid sphere held between the jaws. The correct diameter of the sphere is
JEE Advanced
2021
MSQ
A physical quantity $\overrightarrow S $ is defined as $\overrightarrow S = (\overrightarrow E \times \overrightarrow B )/{\mu _0}$, where $\overrightarrow E $ is electric field, $\overrightarrow B $ is magnetic field and $\mu$0 is the permeability of free space. The dimensions of $\overrightarrow S $ are the same as the dimensions of which of the following quantity(ies)?
JEE Advanced
2020
MSQ
Sometimes it is convenient to construct a system of units so that all quantities can be expressed in
terms of only one physical quantity. In one such system, dimensions of different quantities are given
in terms of a quantity X as follows: [position] = [X$\alpha $]; [speed] = [X$\beta $
]; [acceleration] = [Xp]; [linear
momentum] = [Xq]; [force] = [Xr]. Then
JEE Advanced
2019
MSQ
Let us consider a system of units in which mass and angular momentum are dimensionless. If length has dimension of L, which of the following statement(s) is/are correct?
JEE Advanced
2018
MCQ
If the measurement errors in all the independent quantities are known, then it is possible to determine the error in any dependent quantity. This is done by the use of series expansion and truncating the expansion at the first power of the error. For example, consider the relation $z = x/y.$ If the errors in $x,y$ and $z$ are $\Delta x,\Delta y$ and $\Delta z,$ respectively, then
$$z \pm \Delta z = {{x \pm \Delta x} \over {y \pm \Delta y}} = {x \over y}\left( {1 \pm {{\Delta x} \over x}} \right){\left( {1 \pm {{\Delta y} \over y}} \right)^{ - 1}}.$$
The series expansion for ${\left( {1 \pm {{\Delta y} \over y}} \right)^{ - 1}},$ to first power in $\Delta y/y.$ is $1 \pm \left( {\Delta y/y} \right).$ The relative errors in independent variables are always added. So the error in $z$ will be
$$\Delta z = z\left( {{{\Delta x} \over x} + {{\Delta y} \over y}} \right).$$
The above derivation makes the assumption that $\Delta x/x < < 1,$ $\Delta y/y < < 1.$ Therefore, the higher powers of these quantities are neglected.
Consider the ratio $r = {{\left( {1 - a} \right)} \over {1 + a}}$ to be determined by measuring a dimensionless quantity $a.$ If the error in the measurement of $a$ is $\Delta a\left( {\Delta a/a < < 1.} \right.$ then what is the error $\Delta r$ in determining $r$?
JEE Advanced
2018
MCQ
If the measurement errors in all the independent quantities are known, then it is possible to determine the error in any dependent quantity. This is done by the use of series expansion and truncating the expansion at the first power of the error. For example, consider the relation $z = x/y.$ If the errors in $x,y$ and $z$ are $\Delta x,\Delta y$ and $\Delta z,$ respectively, then
$$z \pm \Delta z = {{x \pm \Delta x} \over {y \pm \Delta y}} = {x \over y}\left( {1 \pm {{\Delta x} \over x}} \right){\left( {1 \pm {{\Delta y} \over y}} \right)^{ - 1}}.$$
The series expansion for ${\left( {1 \pm {{\Delta y} \over y}} \right)^{ - 1}},$ to first power in $\Delta y/y.$ is $1 \pm \left( {\Delta y/y} \right).$ The relative errors in independent variables are always added. So the error in $z$ will be
$$\Delta z = z\left( {{{\Delta x} \over x} + {{\Delta y} \over y}} \right).$$
The above derivation makes the assumption that $\Delta x/x < < 1,$ $\Delta y/y < < 1.$ Therefore, the higher powers of these quantities are neglected.
In an experiment the initial number of radioactive nuclei is $3000.$ It is found that $1000 \pm 40$ nuclei decayed in the first $1.0s.$ For $\left| x \right| < < 1.$ $\ln \left( {1 + x} \right) = x$ up to first power in $x.$ The error $\Delta \lambda ,$ in the determination of the decay constant $\lambda ,$ in ${s^{ - 1}},$ is
JEE Advanced
2017
MCQ
A person measures the depth of a well by measuring the time interval between dropping a stone and receiving the sound of impact with the bottom of the well. The error in his measurement of time is $\delta T = 0.01$ seconds and he measures the depth of the well to be $L=20$ meters. Take the acceleration due to gravity $g = 10m{s^{ - 2}}$ and the velocity of sound is $300$ $m{s^{ - 1}}$. Then the fractional error in the measurement, $\delta L/L,$ is closest to
JEE Advanced
2016
MCQ
There are two Vernier calipers both of which have 1 cm divided into 10 equal divisions on the main scale.
The Vernier scale of one of the calipers (C
1) has 10 equal divisions that correspond to 9 main scale
divisions. The Vernier scale of the other caliper (C
2) has 10 equal divisions that correspond to 11 main
scale divisions. The readings of the two calipers are shown in the figure. The measured values (in cm) by
calipers C
1 and C
2 respectively, are
JEE Advanced
2016
MSQ
In an experiment to determine the acceleration due to gravity g, the formula used for the time period of a
periodic motion is $T = 2\pi \sqrt {{{7\left( {R - r} \right)} \over {5g}}} $. The values of R and r are measured to be (60 $ \pm $ 1) mm and (10 $ \pm $ 1)
mm, respectively. In five successive measurements, the time period is found to be 0.52 s, 0.56 s, 0.57 s,
0.54 s and 0.59 s. The least count of the watch used for the measurement of time period is 0.01 s. Which of
the following statement(s) is(are) true?
JEE Advanced
2016
MSQ
A length-scale (l) depends on the permittivity ($\varepsilon $) of a dielectric material, Boltzmann constant (kB), the absolute temperature (T), the number per unit volume (n) of certain charged particles, and the charge (q) carried by each of the particles. Which of the following expression(s) for I is(are) dimensionally correct?
JEE Advanced
2015
MSQ
Planck's constant h, speed of light c and gravitational constant G are used to form a unit of length L and a
unit of mass M. Then the correct option(s) is(are)
JEE Advanced
2015
MSQ
Consider a Vernier callipers in which each 1 cm on the main scale is divided into 8 equal divisions and a
screw gauge with 100 divisions on its circular scale. In the Vernier callipers, 5 divisions of the Vernier
scale coincide with 4 divisions on the main scale and in the screw gauge, one complete rotation of the
circular scale moves it by two divisions on the linear scale. Then:
JEE Advanced
2013
MCQ
Match
List I with
List II and select the correct answer using the codes given below the lists:
List I
P. Boltzmann Constant
Q. Coefficient of viscosity
R. Plank Constant
S. Thermal conductivity
List II
1. [ML
2T
-1]
2. [ML
-1T
-1]
3. [MLT
-3K
-1]
4. [ML
2T
-2K
-1]
JEE Advanced
2013
MCQ
The diameter of a cylinder is measured using a Vernier callipers with no zero error. It is found that the zero
of the Vernier scale lies between 5.10 cm and 5.15 cm of the main scale. The Vernier scale has 50 divisions
equivalent to 2.45 cm. The 24th division of the Vernier scale exactly coincides with one of the main scale
divisions. The diameter of the cylinder is
JEE Advanced
2012
MCQ
In the determination of Young's modulus $\left( {Y = {{4MLg} \over {\pi l{d^2}}}} \right)$
by using Searle's method, a wire of length L = 2 m
and diameter d = 0.5 mm is used. For a load M = 2.5 kg, an extension l = 0.25 mm in the length of the wire
is observed. Quantities d and l are measured using a screw gauge and a micrometer, respectively. They
have the same pitch of 0.5 mm. The number of divisions on their circular scale is 100. The contributions to
the maximum probable error of the Y measurement
JEE Advanced
2011
MCQ
A dense collection of equal number of electrons and positive ions is called neutral plasma. Certain solids containing
fixed positive ions surrounded by free electrons can be treated as neutral plasma. Let 'N' be the number density of
free electrons, each of mass 'm'. When the electrons are subjected to an electric field, they are displaced relatively
away from the heavy positive ions. If the electric field becomes zero, the electrons begin to oscillate about the
positive ions with a natural angular frequency '${\omega _p}$' which is called the plasma frequency. To sustain the oscillations,
a time varying electric field needs to be applied that has an angular frequency $\omega $, where a part of the energy is
absorbed and a part of it is reflected. As $\omega $ approaches ${\omega _p}$ all the free electrons are set to resonance together and all
the energy is reflected. This is the explanation of high reflectivity of metals.
Taking the electronic charge as 'e' and the permittivity as $'{\varepsilon _0}'$. Use dimensional analysis to determine the
correct expression for ${\omega _p}$.
JEE Advanced
2011
MCQ
The density of a solid ball is to be determined in an experiment. The diameter of the ball is measured with
a screw gauge, whose pitch is 0.5 mm and there are 50 divisions on the circular scale. The reading on the
main scale is 2.5 mm and that on the circular scale is 20 divisions. If the measured mass of the ball has a
relative error of 2 %, the relative percentage error in the density is
JEE Advanced
2010
MCQ
A vernier calipers has 1 mm marks on the main scale. It has 20 equal divisions on the Vernier scale which match with 16 main scale divisions. For this Vernier calipers, the least count is
JEE Advanced
2010
MSQ
A student uses a simple pendulum of exactly 1m length to determine g, the acceleration due to gravity. He
uses a stop watch with the least count of 1 sec for this and records 40 seconds for 20 oscillations. For this
observation, which of the following statement(s) is (are) true?
JEE Advanced
2008
MCQ
Student I, II and III perform an experiment for measuring the acceleration due to gravity (g) using a
simple pendulum. They use different length of the pendulum and/or record time for different number
of oscillations. The observations area shown in the table.
Least count for length = 0.1 cm
Least count for time = 0.1 s
| Student |
Length of the pendulum (cm) |
No. of oscillations (n) |
Total time for(n) oscillations (s) |
Time periods (s) |
| I |
64.0 |
8 |
128.0 |
16.0 |
| II |
64.0 |
4 |
64.0 |
16.0 |
| III |
20.0 |
4 |
36.0 |
9.0 |
If EI, EII and EIII are the percentage errors in g, i.e., $\left(\frac{\triangle g}g\times100\right)$ for students I, II and III, respectively,then
JEE Advanced
2007
MCQ
Some physical quantities are given in
Column I and some possible SI units in which these quantities may be expressed
are given in
Column II. Match the physical quantities in
Column I with the units in
Column II.
Column I
(A) GMeMs ,
G $ \to $ universal gravitational constant, Me $ \to $ mass of the earth,
Ms $ \to $ mass of the Sun
(B) ${{3RT} \over M}$,
R $ \to $ universal gas constant, T $ \to $ absolute temperature,
M $ \to $ molar mass
(C) ${{{F^2}} \over {{q^2}{B^2}}}$ ,
F $ \to $ force, q $ \to $ charge, B $ \to $ magnetic field
(D) ${{G{M_e}} \over {{R_e}}}$,
G $ \to $ universal gravitational constant,
Me $ \to $ mass of the earth, Re $ \to $ radius of the earth
Column II
(p) (volt) (coulomb) (metre)
(q) (kilogram) (metre)3 (second)−2
(r) (meter)2(second)−2
(s) (farad) (volt)2 (kg)−1
JEE Advanced
2007
MCQ
A student performs an experiment to determine the Young's modulus of a wire, exactly 2 m long,
by Searle's method. In a particular reading, the student measures the extension in the length of
the wire to be 0.8 mm with an uncertainty of $\pm0.05\;\mathrm{mm}$ at a load of exactly 1.0 kg. The student
also measures the diameter of the wire to be 0.4 mm with an uncertainty of $\pm0.01\;\mathrm{mm}$. Take
g = 9.8 m/s2
(exact). The Young's modulus obtained from the reading is
JEE Advanced
2006
MCQ
A student performs an experiment for determination of $g\left(=\frac{4 \pi^2 l}{\mathrm{~T}^2}\right), l=1 m$, and he commits an error of $\Delta l$. For T , he takes the time of $n$ oscillations with the stop watch of least count $\Delta \mathrm{T}$ and he commits a human error of 0.1 s . For which of the following data, the measurement of $g$ will be most accurate?
JEE Advanced
2006
MCQ
In a screw gauge, the zero of main scale coincides with the fifth division of circular scale in figure (i).The circular division of screw gauge is 50. It moves 0.5 mm on main scale in one rotation.The diameter of the ball in figure (ii) is
JEE Advanced
2005
MCQ
Which of the following set have different dimensions?
JEE Advanced
2005
MCQ
The side of a cube is measured by vernier
callipers (10 divisions of a vernier scale
coincide with 9 divisions of main scale,
where 1 division of main scale is 1 mm). The
main scale reads 10 mm and first division of
vernier scale coincides with the main scale;
Mass of the cube is 2.736 g. Find the density
of the cube in appropriate significant figures.
JEE Advanced
2004
MCQ
A wire of length $l = 6 \pm 0.06$ cm and $r = 0.5 \pm 0.005$ cm and mass $m = 0.3 \pm 0.003$ gm. Maximum percentage error in density is
JEE Advanced
2004
MCQ
Pressure depends on distance as, $P = {\alpha \over \beta }\exp \left( { - {{\alpha z} \over {k\theta }}} \right)$, where $\alpha $, $\beta $ are constants, z in distance, k is Boltzman's constant and $\theta $ is temperature. The dimention of $\beta $ are
JEE Advanced
2003
MCQ
A cube has a side of length 1.2 ✕ 10-2 m. Calculate its volume.
JEE Advanced
2001
MCQ
A quantity X is given by ${\varepsilon _0}L{{\Delta V} \over {\Delta t}}$ where ${\varepsilon _0}$ is the permittivity of the free space, L is a length, ${\Delta V}$ is a potential difference and ${\Delta t}$ is a time interval. The dimentional formula for X is the same as that of
JEE Advanced
2000
MCQ
The dimension of $\left( {{1 \over 2}} \right){\varepsilon _0}{E^2}$
( ${\varepsilon _0}$ : permittivity of free space, E electric field )
JEE Advanced
1998
MSQ
Let [${\mathrm\varepsilon}_\mathrm o$] denote the dimentional formula of the permittivity of the vacuum, and [$\mu_o$] that of the permeability of the vacuum.If M = mass, L = length, T = time and I = electric current,
JEE Advanced
1998
MSQ
The SI unit of inductance, the henry can be written as
JEE Advanced
1995
MSQ
The pairs of physical quantities that have the same dimensions is (are):
JEE Advanced
1986
MSQ
The dimensions of the quantities in one ( or more ) of the following pairs are the same. Identify the pair(s)