GATE Physics 2025
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Physics (PH)
General Aptitude
Q.1 – Q.5 Carry ONE mark Each
Q.1 Is there any good show _______ television tonight?
Select the most appropriate option to complete the above sentence.
(A) in
(B) at
(C) within
(D) on
Q.2 As the police officer was found guilty of embezzlement, he was _______ dismissed
from the service in accordance with the Service Rules.
Select the most appropriate option to complete the above sentence.
(A) sumptuously
(B) brazenly
(C) unintentionally
(D) summarily
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Q.3 The sum of the following infinite series is:
1 1 1 1 1
+ + + + +⋯
1! 2! 3! 4! 5!
(A) π
(B) 1+e
(C) e−1
(D) e
Q.4 A thin wire is used to construct all the edges of a cube of 1 m side by bending,
cutting and soldering the wire. If the wire is 12 m long, what is the minimum number
of cuts required to construct the wire frame to form the cube?
(A) 3
(B) 4
(C) 6
(D) 12
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Q.5 The figures I, II and III are parts of a sequence. Which one of the following options
comes next in the sequence at IV?
?
I II III IV
(A)
(B)
(C)
(D)
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Q.6 – Q.10 Carry TWO marks Each
Q.6 “Why do they pull down and do away with crooked streets, I wonder, which are my
delight, and hurt no man living? Every day the wealthier nations are pulling down
one or another in their capitals and their great towns: they do not know why they do
it; neither do I. It ought to be enough, surely, to drive the great broad ways which
commerce needs and which are the life-channels of a modern city, without
destroying all history and all the humanity in between: the islands of the past.”
(From Hilaire Belloc’s “The Crooked Streets”)
Based only on the information provided in the above passage, which one of the
following statements is true?
(A) The author of the passage takes delight in wondering.
(B) The wealthier nations are pulling down the crooked streets in their capitals.
(C) In the past, crooked streets were only built on islands.
(D) Great broad ways are needed to protect commerce and history.
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Q.7 Rohit goes to a restaurant for lunch at about 1 PM. When he enters the restaurant,
he notices that the hour and minute hands on the wall clock are exactly coinciding.
After about an hour, when he leaves the restaurant, he notices that the clock hands
are again exactly coinciding. How much time (in minutes) did Rohit spend at the
restaurant?
(A) 6
64 11
(B) 5
66 13
(C) 5
65 11
(D) 6
66 13
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Q.8 A color model is shown in the figure with color codes: Yellow (Y), Magenta (M),
Cyan (Cy), Red (R), Blue (Bl), Green (G), and Black (K).
Which one of the following options displays the color codes that are consistent with
the color model?
(A)
(B)
(C)
(D)
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Q.9 A circle with center at (x, y) = (0.5, 0) and radius = 0.5 intersects with another
circle with center at (x, y) = (1, 1) and radius = 1 at two points. One of the points
of intersection (x, y) is:
(A) (0, 0)
(B) (0.2, 0.4)
(C) (0.5, 0.5)
(D) (1, 2)
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Q.10 An object is said to have an n-fold rotational symmetry if the object, rotated by an
2π
angle of , is identical to the original.
n
Which one of the following objects exhibits 4-fold rotational symmetry about an
axis perpendicular to the plane of the screen?
Note: The figures shown are representative.
(A)
(B)
(C)
(D)
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Q.11 – Q.35 Carry ONE mark Each
Q.11 For a two-dimensional hexagonal lattice with lattice constant a, the atomic density
is
(A) 1
√3a2
(B) 1
√6a2
(C) 4
3√3a2
(D) 1
3√3a2
Q.12 Consider a crystal that has a basis of one atom. Its primitive vectors are ⃗⃗⃗⃗
a1 = aî ,
a
a2 = aĵ , ⃗⃗⃗⃗
⃗⃗⃗⃗ ̂ ̂
a3 = (î + ĵ + k ), where î, ĵ, k are the unit vectors in the x, y and z
2
directions of the Cartesian coordinate system and a is a positive constant. Which
one of the following is the correct option regarding the type of the Bravais lattice?
(A) a3
It is BCC and the volume of the primitive cell is
2
(B) a3
It is FCC and the volume of the primitive cell is
4
(C) a3
It is BCC and the volume of the primitive cell is
8
(D) It is FCC and the volume of the primitive cell is a3
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Q.13 1
A particle of mass m is in a potential V(x) = 2 mω2 x 2 for x > 0 and V(x) = ∞ for
x ≤ 0, where ω is the angular frequency. The ratio of the energies corresponding
to the lowest energy level to the next higher level is
(A) 3
7
(B) 1
2
(C) 1
3
(D) 3
5
Q.14 A particle is scattered from a potential V(r) = gδ 3 (r), where g is a positive
constant. Using the first Born approximation, the angular (θ, φ) dependence of
dσ
differential scattering cross section is
dΩ
(A) Independent of θ but dependent on φ
(B) Dependent on θ but independent of φ
(C) Dependent on both θ and φ
(D) Independent of both θ and φ
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Q.15 The Joule-Thomson expansion of a gas is
(A) Isentropic
(B) Isenthalpic
(C) Isobaric
(D) Isochoric
Q.16 Which one of the following is correct for the phase velocity vp and group velocity
vg ? (c is the speed of light in vacuum)
(A) For matter waves in the relativistic case, vp vg > c 2
(B) For electromagnetic waves in a medium, vp represents the speed with which energy
propagates
(C) For electromagnetic waves in a medium, both vp and vg can be more than c
(D) For matter waves in free space, vp ≠ vg
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Q.17 As per the Drude model of metals, the electrical resistance of a metallic wire of
length L and cross-section area A is
(Consider τ as the relaxation time, m as electron mass, n as carrier concentration
and e as electronic charge)
(A) mL
ne 2 Aτ
(B) 2mL
ne 2 Aτ
(C) mL
2ne 2 Aτ
(D) mL
4ne 2 Aτ
Q.18 Which one of the following baryons has strangeness quantum number S = −1?
(A) Σ ∗0
(B) n
(C) Ξ ∗0
(D) Δ0
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Q. 19 A logic gate circuit is shown in the figure below. The correct combination for the
input (P, Q) for which the output T = 1 is
(A) (0,0)
(B) (0,1)
(C) (1,1)
(D) (1,0)
Q.20 The nuclear energy levels of mirror nuclei are similar. Using this empirical fact
alone, the nuclear force can be said to be independent of which one of the following
properties of the nucleons?
(A) Mass
(B) Spin
(C) Charge
(D) Parity
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Q.21 1
Consider the function f(z) = of a complex variable z. The residues of
z 2 (z−2)3
the function at z = 0 and z = 2, respectively, are
(A) 3 3
− and
8 8
(B) 3 3
and −
8 16
(C) 3 3
− and
16 16
(D) 3 3
− and
8 16
Q.22 Consider one mole of a monovalent metal at absolute zero temperature, obeying the
free electron model. Its Fermi energy is EF . The energy corresponding to the filling
NA
of electrons, where NA is the Avogadro number, is 2n EF . The value of n is
2
(A) 2
−
3
(B) 2
+
3
(C) 1
−
3
(D) −1
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Q.23 A paramagnetic material containing paramagnetic ions with total angular
1
momentum J = is kept at absolute temperature T. The ratio of the magnetic field
2
required for 80% of the ions to be in the lowest energy state to that required for
having 60% of the ions to be in the lowest energy state at the same temperature is
(A) 2ln2
3
ln (2)
(B) ln2
3
ln (2)
(C) 3ln2
3
ln (2)
(D) ln3
3
ln (2)
Q.24 Which of the following option(s) is/are correct for the ground state of a hydrogen
atom?
(A) Linear Stark effect is zero
(B) It has definite parity
(C) Spin-orbit coupling is zero
(D) Hyperfine splitting is zero
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Q.25 Which of the following option(s) is/are correct for photons?
(A) Its rest mass is zero, but its energy is non-zero
(B) It carries non-zero linear momentum
(C) It carries zero spin angular momentum
(D) It has two linearly independent states of polarization
Q.26 A schematic Pressure-Temperature diagram of water is shown in the figure. Which
of the following option(s) is/are correct?
(A) Clausius-Clapeyron equation is valid across the melting curve and the vaporization
curve
(B) Melting curve has the highest slope
(C) The critical point exists only for the vaporization curve
(D) Clausius-Clapeyron equation is not valid across the melting curve and the
vaporization curve
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Q.27 Which of the following consideration(s) is/are showing that nuclear beta decay,
n → p + e − + ν̅e , has to be a three-body decay?
(A) Continuous distribution of the electron energy
(B) Spin of the final state
(C) Mass of the electron
(D) Mass of the proton
Q.28 Potential energy of two diatomic molecules P and Q of the same reduced mass is
shown in the figure. According to this diagram, which of the following option(s)
is/are correct?
(A) The equilibrium inter-nuclear distance of Q is more than that of P
(B) The total energy E = 0 separates bound and unbound states of the molecules
(C) The lowest vibrational frequency of P is larger than that of Q
(D) Dissociation energy of Q is more than that of P
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Q.29 Nuclear radiation emitted from a 60Co radioactive source is detected by a
photomultiplier tube (PMT) coupled to a scintillator crystal. Which of the following
option(s) is/are correct?
(A) γ radiation from 60Co will directly hit the photocathode of the PMT without
interacting with the scintillator crystal and produce a signal
(B) β radiation from 60Co source interacts with the scintillator crystal, producing γ
radiation, which will hit the photocathode of the PMT and produce a signal
(C) A mu-metal shield is put all around the PMT to nullify the effect of external electric
fields
(D) A mu-metal shield is put all around the PMT to nullify the effect of external
magnetic fields
Q.30 One mole of an ideal monatomic gas at absolute temperature T undergoes free
expansion to double its original volume, so that the entropy change is ΔS1 . An
identical amount of the same gas at absolute temperature 2T undergoes isothermal
expansion to double its original volume, so that the entropy change is ΔS2. The
ΔS1
value of (in integer) is ____
ΔS2
Q.31 A linear dielectric sphere of radius R has a uniform frozen-in polarization along the
z-axis. The center of the sphere initially coincides with the origin, about which the
electric dipole moment is p1. When the sphere is shifted to the point (2R, 0, 0), the
|p1 |
corresponding dipole moment with respect to the origin is p2 . The value of
|p2 |
(in integer) is _____
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Q.32 The effective magnetic moment (in units of Bohr magneton) for the ground state of
an isolated 4f ion with 6 unpaired electrons in the 4f shell according to Hund’s
rules is (in integer) _____
Q.33 Powder X-ray diffraction pattern of a cubic solid with lattice constant a has the
(111) diffraction peak at θ = 30°. If the lattice expands such that the lattice constant
becomes 1.25a, the angle (in degrees) corresponding to the (111) peak changes to
1
sin−1 ( ). The value of n (rounded off to one decimal place) is _____
n
Q.34 Consider a monatomic chain of length 30 cm. The phonon density of states is
1.2 × 10−4 s. Assuming the Debye model, the velocity of sound in m/s (rounded
off to one decimal place) is _____
Q.35 3
The Δ+ baryon with spin , at rest, decays to a proton and a pion (Δ+ → p + π 0 ).
2
The Δ+ has positive intrinsic parity and π 0 has negative intrinsic parity. The orbital
angular momentum of the proton-pion system (in integer) is _____
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Q.36 – Q.55 Carry TWO marks Each
Q.36 The screened nuclear charge of neutral Helium atom is given as 1.7e, where e is
the magnitude of the electronic charge. Assuming the Bohr model of the atom for
Z2 1
which the energy levels are En = − atomic units (Z is the atomic number),
2 n2
the first ionization potential of Helium in atomic units is
(A) 0.89
(B) 1.78
(C) 0.94
(D) 3.16
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Q.37 The wire loop shown in the figure carries a steady current I. Each straight section
of the loop has length d. A part of the loop lies in xy plane and the other part is
tilted at 30° with respect to the xz plane. The magnitude of the magnetic dipole
moment of the loop (in appropriate units) is
(A) √2 Id 2
(B) 2 Id2
(C) √3 Id 2
(D) Id2
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Q.38 The figure shows a system of two equal masses m and three massless horizontal
springs with spring constants k1 , k2 , k1 . Ignore gravity. The masses can move only
in the horizontal direction and there is no dissipation. If m = 1, k1 = 2 and k2 = 3
(all in appropriate units), the frequencies of the normal modes of the system in the
same system of units are
(A) √2 , √8
(B) √2 , √6
(C) √3 , √10
(D) √3 , √8
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Q.39 Two projectile protons P1 and P2 both with spin up (along the +z direction) are
scattered from another fixed target proton T with spin up at rest in the xy plane, as
shown in the figure. They scatter one at a time. The nuclear interaction potential
⃗ ⋅ S, where L
between both the projectiles and the target proton is λL ⃗ is the orbital
angular momentum of the system with respect to the target, S is the spin angular
momentum of the system and λ is a negative constant in appropriate units. Which
one of the following is correct?
(A) P1 will be scattered in the +y direction (upward) and P2 will be scattered in the −y
direction (downward)
(B) P1 will be scattered in the +y direction (upward) and P2 will be scattered in the
+y direction (upward)
(C) P1 will be scattered in the −y direction (downward) and P2 will be scattered in the
+y direction (upward)
(D) P1 will be scattered in the −y direction (downward) and P2 will be scattered in
the −y direction (downward)
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Q.40 A thin circular ring of radius R lies in the xy plane with its centre coinciding with
the origin. The ring carries a uniform line charge density λ. The quadrupole
contribution to the electrostatic potential at the point (0, 0, d), where d ≫ R, is
(A) λR 3
−
4ε0 d3
(B) 0
(C) λR 3
4ε0 d3
(D) λR 3
−
2ε0 d3
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Q.41 An α particle is scattered from an Au target at rest as shown in the figure. D1 and
D2 are the detectors to detect the scattered α particle at an angle θ and along the
beam direction, respectively, as shown. The signals from D1 and D2 are converted
to logic signals and fed to logic gates. When a particle is detected, the signal is 1
and is 0 otherwise. Which one of the following circuits detects the particle scattered
at the angle θ only?
(A)
(B)
(C)
(D)
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Q.42 Consider a two-level system with energy states +ε and – ε . The number of
particles at +ε level is N+ and the number of particles at – ε level is N− . The total
energy of the system is E and the total number of particles is N = N+ + N− . In the
thermodynamic limit, the inverse of the absolute temperature of the system is
(Given: ln N! ≃ N ln N − N)
(A) E
kB N−
ε
ln [ E ]
2ε N+
ε
(B) kB
lnN
ε
(C) kB
lnN
2ε
(D) E
kB N−
ε
ln [ E ]
ε N+
ε
Q.43 Let |m〉 and |n〉 denote the energy eigenstates of a one-dimensional simple
harmonic oscillator. The position and momentum operators are X̂ and P̂,
respectively. The matrix element 〈m|P̂X̂|n〉 is non-zero when
(A) m = n ± 2 only
(B) m = n or m = n ± 2
(C) m = n ± 3 only
(D) m = n ± 1 only
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Q.44 A two-level quantum system has energy eigenvalues E1 and E2 . A perturbing
potential H ′ = λΔσx is introduced, where Δ is a constant having dimensions of
0 1
energy, λ is a small dimensionless parameter, and σx = ( ). The magnitudes of
1 0
′
the first and the second order corrections to E1 due to H , respectively, are
(A) λ2 Δ2
0 and
|E1 −E2 |
(B) |λΔ| λ2 Δ2
and
2 |E1 −E2 |
(C) λ2 Δ2
|λΔ| and
|E1 −E2 |
(D) 1 λ2 Δ2
0 and
2 |E1 −E2 |
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Q.45 1
An electron with mass m and charge q is in the spin up state ( ) at time t = 0. A
0
constant magnetic field is applied along the y-axis, B = B0 ĵ, where B0 is a
qB0
constant. The Hamiltonian of the system is H = − ℏωσy , where ω = > 0 and
2m
0 −i
σy = ( ). The minimum time after which the electron will be in the spin down
i 0
1 1
state along the x-axis, i.e., ( ) , is
√2 −1
(A) π
8ω
(B) π
4ω
(C) π
2ω
(D) π
ω
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Q.46 1
A system of three non-identical spin particles has the Hamiltonian
2
A
H = ℏ2 ( S1 + S2 ) ⋅ S3, where S1, S2 and S3 are the spin operators of particles
labelled 1, 2 and 3 respectively and A is a constant with appropriate dimensions.
The set of possible energy eigenvalues of the system is
(A) A
0, , −A
2
(B) A A
0, , −
2 2
(C) 3A A
0, ,−
2 2
(D) 3A A
0, − ,
2 2
Q.47 Which of the following option(s) is/are correct for a Type I superconductor?
(A) The phase transition to the normal state in the absence of a magnetic field is of
second order
(B) With increase in temperature, the critical magnetic field decreases linearly to zero
(C) Below the critical temperature, the entropy in the superconducting state is less than
that in the normal state
(D) The phase transition to the normal state in the presence of a magnetic field is of first
order
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Q.48 Consider two hypothetical nuclei X1 and X2 undergoing β decay, resulting in nuclei
Y1 and Y2 , respectively. The decay scheme and the corresponding JP values of the
nuclei are given in the figure. Which of the following option(s) is/are correct? (J is
the total angular momentum and P is parity)
(A) X1 → Y1 is Fermi transition and X2 → Y2 is Fermi transition
(B) X1 → Y1 is Fermi transition and X2 → Y2 is Gamow-Teller transition
(C) X1 → Y1 is Gamow-Teller transition and X2 → Y2 is Fermi transition
(D) X1 → Y1 is Gamow-Teller transition and X2 → Y2 is Gamow-Teller transition
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Q.49 A point charge q is placed at a distance d above an infinite, grounded conducting
plate placed on the xy plane at z = 0. The electrostatic potential in z > 0 region is
1 q
given by φ = φ1 + φ2 , where φ1 = 2 2 2
and
4πε0 √x +y +(z−d)
1 q
φ2 = − . Which of the following option(s) is/are correct?
4πε0 √x 2 +y 2 +(z+d)2
(A) 1 q
The magnitude of the force experienced by the point charge q is
16πε0 d 2
(B) 1 q2
The electrostatic energy of the system is
8πε0 d
(C) 1
The induced surface charge density on the plate is proportional to
√x 2 +y 2 +d 2
(D) The electrostatic potential φ1 satisfies Poisson’s equation for z > 0
Q.50 In coordinates (t , x), a contravariant second rank tensor A has non-zero diagonal
components Att = P and Axx = Q, with all other components vanishing, and P, Q
being real constants. Here, t is time and x is space coordinate. Consider a Lorentz
transformation (t, x) → (t ′ , x ′ ) to another frame that moves with relative speed v in
tt xx
the +x direction, so that A → A′ . If A′ and A′ are the diagonal components of
1
A′ , then setting the speed of light c = 1, and with γ = , which of the
√1−v 2
following option(s) is/are correct?
(A) A′tt = γ 2 P + γ 2 v 2 Q
(B) A′tt = γ 2 v 2 P + v 2 Q
(C) A′xx = γ 2 v 2 P + γ 2 Q
(D) A′xx = v 2 P + γ 2 Q
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Q.51 The Lagrangian of a particle of mass m and charge q moving in a uniform magnetic
field of magnitude 2B that points in the z direction, is given by
m
L = 2 v 2 + qB(xvy − yvx ) where vx , vy , vz are the components of its velocity v.
If px , py , pz denote the conjugate momenta in the x, y, z directions and H is the
Hamiltonian, which of the following option(s) is/are correct ?
(A) dx 1
= (p − qBy)
dt m x
(B) dpx qB
= (p − qBx)
dt m y
(C) dpy qB
= − (p + qBy)
dt m x
(D) 1 2
H= [(px + qBy)2 + (py − qBx) + pz2 ]
2m
Q.52 A bead is constrained to move along a long, massless, frictionless horizontal rod
parallel to the x axis. The rod itself is moving vertically upward along the
z direction against gravity with a constant speed, starting from z = 0 at t = 0, and
remains horizontal. The conjugate momenta are denoted by px , py , pz and the
Hamiltonian by H. Which of the following option(s) is/are correct?
(A) H is the total energy of the system and is conserved
(B) H is the total energy of the system and is not conserved
(C) H is not the total energy of the system, but it is conserved
(D) H is not the total energy of the system and is not conserved
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Q.53 In a one-dimensional Hamiltonian system with position q and momentum p,
1
consider the canonical transformation (q , p) → (Q = , P = q p2 ), where Q
p
and P are the new position and momentum, respectively. Which of the following
option(s) regarding the generating function F is/are correct?
(A) q
F = F1 (q, Q) =
Q
(B) F = F2 (q, P) = √Pq
(C) p
F = F3 (p, Q) = 2
Q
(D) P
F = F4 (p, P) =
p
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Q.54 The energy of a free, relativistic particle of rest mass m moving along the x axis in
one dimension, is denoted by T. When moving in a given potential V(x), its
Hamiltonian is H = T + V(x). In the presence of this potential, its speed is v,
conjugate momentum p, and the Lagrangian L. Then, which of the following
option(s) is/are correct?
(A)
p2
H = c 2 √m 2 + + V(x)
c2
(B) pc
v =
√p2 + m2 c 2
(C)
v2
L = mc 2 √1 − − V(x)
c2
(D)
v2
L = − mc 2 √1 − − V(x)
c2
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Q.55 Consider the integral
1 z4 − 1
I= ∮ dz,
2πi (z − a ) (z − b )
b a
where z is a complex variable and a, b are positive real numbers. The integral is
taken over a unit circle with center at the origin. Which of the following option(s)
is/are correct?
(A) 5
I= when a = 1, b = 2
8
(B) 10
I= when a = 1, b = 3
3
(C) 5
I= when a = 2, b = 1
8
(D) 5
I= when a = 3, b = 2
8
Q.56 A neutral conducting sphere of radius R is placed in a uniform electric field of
magnitude E0 , that points along the z axis. The electrostatic potential at any point r
R3
outside the sphere is given by V(r, θ) = V0 − E0 r (1 − r 3 ) cos θ, where V0 is the
constant potential of the sphere. Which of the following option(s) is/are correct?
(A) The induced surface charge density on the sphere is proportional to sin θ
(B) As r → ∞, E⃗ = E0 cos θ r̂
(C) The electric field at any point is curl free for r > R
(D) The electric field at any point is divergence free for r > R
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Physics (PH)
Q.57 A point charge q is placed at the origin, inside a linear dielectric medium of infinite
extent, having relative permittivity εr . Which of the following option(s) is/are
correct?
(A) 1
The magnitude of the polarization varies as
r2
(B) 1
The magnitude of the polarization varies as
r3
(C) The magnitude of the screened charge due to the dielectric medium is less than the
magnitude of the point charge q for εr > 1
(D) The magnitude of the screened charge due to the dielectric medium is more than the
magnitude of the point charge q for εr = 1
Q.58 A linear magnetic material in the form of a cylinder of radius R and length L is
placed with its axis parallel to the z axis. The cylinder has uniform magnetization
Mk̂. Which of the following option(s) is/are correct?
(A) The magnetic field at any point outside the cylinder can be expressed as the gradient
of a scalar function
(B) The bound volume current density is zero
(C) The surface current density on the curved surface is non-zero
(D) The surface current densities on the flat surfaces (top and bottom) are non-zero
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Organizing Institute: IIT Roorkee
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Physics (PH)
Q.59 Cyclotrons are used to accelerate ions like deuterons (d) and α particles. Keeping
the magnetic field same for both, d and α are extracted with energies 10 MeV and
20 MeV with extraction radii rd and rα , respectively. Taking the masses
rα
Md = 2000 MeV/c 2 and Mα = 4000 MeV/c 2 , the value of (in integer) is
rd
______
Q.60 In the transistor circuit shown in the figure, VBE = 0.7 V and βDC = 400. The value
of the base current in μA (rounded off to one decimal place) is ___________
Q.61 Consider the set {1, x, x 2 }. An orthonormal basis in x ∈ [−1,1] is formed from
these three terms, where the normalization of a function f(x) is defined via
1
∫−1 x 2 [f(x)]2 dx = 1. If the orthonormal basis set is
3 5 1 21
(√ , √ x , √ (5x 2 − 3)) , then the value of N (in integer) is ______
2 2 2 N
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Organizing Institute: IIT Roorkee
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Physics (PH)
The Hamiltonian for a one dimensional system with mass m, position q and
Q.62 p2
momentum p is H(p, q) = + q 2 A(q), where A(q) is a real function of q. If
2m
d2q dA(q) A(q)
m = −5qA(q), then =n . The value of n (in integer) is ______
dt 2 dq q
3
A system of five identical, non-interacting particles with mass m and spin is
Q.63 2
confined to a one-dimensional potential well of length L. If the lowest energy of the
π 2 ℏ2
system is N , the value of N (in integer) is _____
2mL2
Q.64 A wheel of mass 4M and radius R is made of a thin uniform distribution of mass
3M at the rim and a point mass M at the center. The spokes of the wheel are
massless. The center of mass of the wheel is connected to a horizontal massless rod
of length 2R, with one end fixed at O, as shown in the figure. The wheel rolls
⃗ is the total angular
without slipping on horizontal ground with angular speed Ω. If L
⃗
dL
momentum of the wheel about O, then the magnitude | | = N(MR2 Ω2 ). The
dt
value of N (in integer) is ____
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Organizing Institute: IIT Roorkee
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Physics (PH)
The figure shows an opamp circuit with a 5.1 V Zener diode in the feedback loop.
Q.65 The opamp runs from ±15 V supplies. If a +1V signal is applied at the input, the
output voltage (rounded off to one decimal place) is ____
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Organizing Institute: IIT Roorkee
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Answer Key for Physics (PH)
Q. No. Session Q. Type Section Key/Range Marks
1 7 MCQ GA D 1
2 7 MCQ GA D 1
3 7 MCQ GA C 1
4 7 MCQ GA A 1
5 7 MCQ GA B 1
6 7 MCQ GA B 2
7 7 MCQ GA C 2
8 7 MCQ GA A 2
9 7 MCQ GA B 2
10 7 MCQ GA B 2
11 7 MCQ PH C 1
12 7 MCQ PH A 1
13 7 MCQ PH A 1
14 7 MCQ PH D 1
15 7 MCQ PH B 1
16 7 MCQ PH D 1
17 7 MCQ PH A 1
18 7 MCQ PH A 1
19 7 MCQ PH A 1
20 7 MCQ PH C 1
21 7 MCQ PH C 1
22 7 MCQ PH A 1
23 7 MCQ PH A 1
24 7 MSQ PH A;B;C 1
25 7 MSQ PH A;B;D 1
26 7 MSQ PH A;B;C 1
27 7 MSQ PH A;B 1
28 7 MSQ PH A;B;C 1
29 7 MSQ PH B;D 1
30 7 NAT PH 1 to 1 1
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31 7 NAT PH 1 to 1 1
32 7 NAT PH 0 to 0 1
33 7 NAT PH 2.5 to 2.5 1
34 7 NAT PH 794.0 to 797.0 1
35 7 NAT PH 1 to 1 1
36 7 MCQ PH A 2
37 7 MCQ PH D 2
38 7 MCQ PH A 2
39 7 MCQ PH B 2
40 7 MCQ PH A 2
41 7 MCQ PH A 2
42 7 MCQ PH A 2
43 7 MCQ PH B 2
44 7 MCQ PH A 2
45 7 MCQ PH B 2
46 7 MCQ PH A 2
47 7 MSQ PH A;C;D 2
48 7 MSQ PH B 2
49 7 MSQ PH D 2
50 7 MSQ PH A;C 2
51 7 MSQ PH B;C;D 2
52 7 MSQ PH D 2
53 7 MSQ PH A;D 2
54 7 MSQ PH A;B;D 2
55 7 MSQ PH A;C 2
56 7 MSQ PH C;D 2
57 7 MSQ PH A;C 2
58 7 MSQ PH A;B;C 2
59 7 NAT PH 1 to 1 2
60 7 NAT PH 18 to 19 2
61 7 NAT PH 6 to 6 2
62 7 NAT PH 3 to 3 2
63 7 NAT PH 8 to 8 2
64 7 NAT PH 6 to 6 2
65 7 NAT PH 7.0 to 7.2 2
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Source: GATE. Question paper published by GATE.