Rotational Motion: JEE Mains Previous Year Questions (2021-2024) | Physics for JEE Main & Advanced PDF Download

 Page 1


 
 
2024 
 
Q1 - 2024 (01 Feb Shift 1) 
A ball of mass 0.5kg is attached to a string of length 50cm. The ball is rotated on a 
horizontal circular path about its vertical axis. The maximum tension that the string can 
bear is 400N. The maximum possible value of angular velocity of the ball in rad/s is,: 
(1) 1600 
(2) 40 
(3) 1000 
(4) 20 
Q2 - 2024 (01 Feb Shift 2) 
A disc of radius ?? and mass ?? is rolling horizontally without slipping with speed ?? . It then 
moves up an inclined smooth surface as shown in figure. The maximum height that the 
disc can go up the incline is : 
 
(1) 
?? 2
?? 
(2) 
3
4
?? 2
?? 
(3) 
1
2
?? 2
?? 
(4) 
2
3
?? 2
?? 
Page 2


 
 
2024 
 
Q1 - 2024 (01 Feb Shift 1) 
A ball of mass 0.5kg is attached to a string of length 50cm. The ball is rotated on a 
horizontal circular path about its vertical axis. The maximum tension that the string can 
bear is 400N. The maximum possible value of angular velocity of the ball in rad/s is,: 
(1) 1600 
(2) 40 
(3) 1000 
(4) 20 
Q2 - 2024 (01 Feb Shift 2) 
A disc of radius ?? and mass ?? is rolling horizontally without slipping with speed ?? . It then 
moves up an inclined smooth surface as shown in figure. The maximum height that the 
disc can go up the incline is : 
 
(1) 
?? 2
?? 
(2) 
3
4
?? 2
?? 
(3) 
1
2
?? 2
?? 
(4) 
2
3
?? 2
?? 
Q3 - 2024 (27 Jan Shift 1) 
Four particles each of mass 1kg are placed at four corners of a square of side 2m. 
Moment of inertia of system about an axis perpendicular to its plane and passing 
through one of its vertex is _____kgm
2
. 
 
Q4 - 2024 (27 Jan Shift 2) 
A ring and a solid sphere roll down the same inclined plane without slipping. They start 
from rest. The radii of both bodies are identical and the ratio of their kinetic energies is 
7
x
 
where x ______ is 
Q5 - 2024 (29 Jan Shift 1) 
A cylinder is rolling down on an inclined plane of inclination 60
°
. It's acceleration during 
rolling down will be 
x
 3
m/s
2
, where x = (use g = 10m/s
2
). 
Q6 - 2024 (29 Jan Shift 2) 
A body of mass 5kg moving with a uniform speed 3 2ms
-1
 in X- Y plane along the line 
y = x + 4. The angular momentum of the particle about the origin will be kgm
2
s
-1
. 
Q7 - 2024 (30 Jan Shift 1) 
Consider a Disc of mass 5kg, radius 2m, rotating with angular velocity of 10rad/s about 
an axis perpendicular to the plane of rotation. An identical disc is kept gently over the 
rotating disc along the same axis. The energy dissipated so that both the discs continue 
to rotate together without slipping is J. 
Page 3


 
 
2024 
 
Q1 - 2024 (01 Feb Shift 1) 
A ball of mass 0.5kg is attached to a string of length 50cm. The ball is rotated on a 
horizontal circular path about its vertical axis. The maximum tension that the string can 
bear is 400N. The maximum possible value of angular velocity of the ball in rad/s is,: 
(1) 1600 
(2) 40 
(3) 1000 
(4) 20 
Q2 - 2024 (01 Feb Shift 2) 
A disc of radius ?? and mass ?? is rolling horizontally without slipping with speed ?? . It then 
moves up an inclined smooth surface as shown in figure. The maximum height that the 
disc can go up the incline is : 
 
(1) 
?? 2
?? 
(2) 
3
4
?? 2
?? 
(3) 
1
2
?? 2
?? 
(4) 
2
3
?? 2
?? 
Q3 - 2024 (27 Jan Shift 1) 
Four particles each of mass 1kg are placed at four corners of a square of side 2m. 
Moment of inertia of system about an axis perpendicular to its plane and passing 
through one of its vertex is _____kgm
2
. 
 
Q4 - 2024 (27 Jan Shift 2) 
A ring and a solid sphere roll down the same inclined plane without slipping. They start 
from rest. The radii of both bodies are identical and the ratio of their kinetic energies is 
7
x
 
where x ______ is 
Q5 - 2024 (29 Jan Shift 1) 
A cylinder is rolling down on an inclined plane of inclination 60
°
. It's acceleration during 
rolling down will be 
x
 3
m/s
2
, where x = (use g = 10m/s
2
). 
Q6 - 2024 (29 Jan Shift 2) 
A body of mass 5kg moving with a uniform speed 3 2ms
-1
 in X- Y plane along the line 
y = x + 4. The angular momentum of the particle about the origin will be kgm
2
s
-1
. 
Q7 - 2024 (30 Jan Shift 1) 
Consider a Disc of mass 5kg, radius 2m, rotating with angular velocity of 10rad/s about 
an axis perpendicular to the plane of rotation. An identical disc is kept gently over the 
rotating disc along the same axis. The energy dissipated so that both the discs continue 
to rotate together without slipping is J. 
 
Q8 - 2024 (30 Jan Shift 2) 
Two discs of moment of inertia ?? 1
= 4kgm
2
 and ?? 2
= 2kgm
2
 about their central axes \& 
normal to their planes, rotating with angular speeds 10rad/s\ &4?? ?? ?? /?? respectively are 
brought into contact face to face with their axe of rotation coincident. The loss in kinetic 
energy of the system in the process is  _______J. 
 
Q9 - 2024 (31 Jan Shift 2) 
A body of mass ' ?? ' is projected with a speed ' ?? ' making an angle of 45
°
 with the 
ground. The angular momentum of the body about the point of projection, at the highest 
point is expressed as 
 2mu
3
Xg
. The value of ' X
'
 is 
Q10 - 2024 (31 Jan Shift 2) 
Two identical spheres each of mass 2kg and radius 50cm are fixed at the ends of a light 
rod so that the separation between the centers is 150cm. Then, moment of inertia of the 
system about an axis perpendicular to the rod and passing through its middle point is 
?? 20
kgm
2
, where the value of x is 
Answer Key 
Page 4


 
 
2024 
 
Q1 - 2024 (01 Feb Shift 1) 
A ball of mass 0.5kg is attached to a string of length 50cm. The ball is rotated on a 
horizontal circular path about its vertical axis. The maximum tension that the string can 
bear is 400N. The maximum possible value of angular velocity of the ball in rad/s is,: 
(1) 1600 
(2) 40 
(3) 1000 
(4) 20 
Q2 - 2024 (01 Feb Shift 2) 
A disc of radius ?? and mass ?? is rolling horizontally without slipping with speed ?? . It then 
moves up an inclined smooth surface as shown in figure. The maximum height that the 
disc can go up the incline is : 
 
(1) 
?? 2
?? 
(2) 
3
4
?? 2
?? 
(3) 
1
2
?? 2
?? 
(4) 
2
3
?? 2
?? 
Q3 - 2024 (27 Jan Shift 1) 
Four particles each of mass 1kg are placed at four corners of a square of side 2m. 
Moment of inertia of system about an axis perpendicular to its plane and passing 
through one of its vertex is _____kgm
2
. 
 
Q4 - 2024 (27 Jan Shift 2) 
A ring and a solid sphere roll down the same inclined plane without slipping. They start 
from rest. The radii of both bodies are identical and the ratio of their kinetic energies is 
7
x
 
where x ______ is 
Q5 - 2024 (29 Jan Shift 1) 
A cylinder is rolling down on an inclined plane of inclination 60
°
. It's acceleration during 
rolling down will be 
x
 3
m/s
2
, where x = (use g = 10m/s
2
). 
Q6 - 2024 (29 Jan Shift 2) 
A body of mass 5kg moving with a uniform speed 3 2ms
-1
 in X- Y plane along the line 
y = x + 4. The angular momentum of the particle about the origin will be kgm
2
s
-1
. 
Q7 - 2024 (30 Jan Shift 1) 
Consider a Disc of mass 5kg, radius 2m, rotating with angular velocity of 10rad/s about 
an axis perpendicular to the plane of rotation. An identical disc is kept gently over the 
rotating disc along the same axis. The energy dissipated so that both the discs continue 
to rotate together without slipping is J. 
 
Q8 - 2024 (30 Jan Shift 2) 
Two discs of moment of inertia ?? 1
= 4kgm
2
 and ?? 2
= 2kgm
2
 about their central axes \& 
normal to their planes, rotating with angular speeds 10rad/s\ &4?? ?? ?? /?? respectively are 
brought into contact face to face with their axe of rotation coincident. The loss in kinetic 
energy of the system in the process is  _______J. 
 
Q9 - 2024 (31 Jan Shift 2) 
A body of mass ' ?? ' is projected with a speed ' ?? ' making an angle of 45
°
 with the 
ground. The angular momentum of the body about the point of projection, at the highest 
point is expressed as 
 2mu
3
Xg
. The value of ' X
'
 is 
Q10 - 2024 (31 Jan Shift 2) 
Two identical spheres each of mass 2kg and radius 50cm are fixed at the ends of a light 
rod so that the separation between the centers is 150cm. Then, moment of inertia of the 
system about an axis perpendicular to the rod and passing through its middle point is 
?? 20
kgm
2
, where the value of x is 
Answer Key 
Q1 (2)  
Q2 (3)  
Q3 (16)  
Q4 (7)  
Q5 (10)  
Q6 (60)  
Q7 (250)  
Q8 (24)  
Q9 (8)  
Q10 (53) 
 
Solutions 
Q1 
T = m?? 2
l 
400 = 0.5?? 2
× 0.5 
?? = 40rad/s. 
Q2 
Only the translational kinetic energy of disc changes into gravitational potential energy. 
And rotational KE remains unchanged as there is no friction. 
1
2
?? ?? 2
=?? ?? ?? 
?? =
?? 2
2?? 
Q3 
Page 5


 
 
2024 
 
Q1 - 2024 (01 Feb Shift 1) 
A ball of mass 0.5kg is attached to a string of length 50cm. The ball is rotated on a 
horizontal circular path about its vertical axis. The maximum tension that the string can 
bear is 400N. The maximum possible value of angular velocity of the ball in rad/s is,: 
(1) 1600 
(2) 40 
(3) 1000 
(4) 20 
Q2 - 2024 (01 Feb Shift 2) 
A disc of radius ?? and mass ?? is rolling horizontally without slipping with speed ?? . It then 
moves up an inclined smooth surface as shown in figure. The maximum height that the 
disc can go up the incline is : 
 
(1) 
?? 2
?? 
(2) 
3
4
?? 2
?? 
(3) 
1
2
?? 2
?? 
(4) 
2
3
?? 2
?? 
Q3 - 2024 (27 Jan Shift 1) 
Four particles each of mass 1kg are placed at four corners of a square of side 2m. 
Moment of inertia of system about an axis perpendicular to its plane and passing 
through one of its vertex is _____kgm
2
. 
 
Q4 - 2024 (27 Jan Shift 2) 
A ring and a solid sphere roll down the same inclined plane without slipping. They start 
from rest. The radii of both bodies are identical and the ratio of their kinetic energies is 
7
x
 
where x ______ is 
Q5 - 2024 (29 Jan Shift 1) 
A cylinder is rolling down on an inclined plane of inclination 60
°
. It's acceleration during 
rolling down will be 
x
 3
m/s
2
, where x = (use g = 10m/s
2
). 
Q6 - 2024 (29 Jan Shift 2) 
A body of mass 5kg moving with a uniform speed 3 2ms
-1
 in X- Y plane along the line 
y = x + 4. The angular momentum of the particle about the origin will be kgm
2
s
-1
. 
Q7 - 2024 (30 Jan Shift 1) 
Consider a Disc of mass 5kg, radius 2m, rotating with angular velocity of 10rad/s about 
an axis perpendicular to the plane of rotation. An identical disc is kept gently over the 
rotating disc along the same axis. The energy dissipated so that both the discs continue 
to rotate together without slipping is J. 
 
Q8 - 2024 (30 Jan Shift 2) 
Two discs of moment of inertia ?? 1
= 4kgm
2
 and ?? 2
= 2kgm
2
 about their central axes \& 
normal to their planes, rotating with angular speeds 10rad/s\ &4?? ?? ?? /?? respectively are 
brought into contact face to face with their axe of rotation coincident. The loss in kinetic 
energy of the system in the process is  _______J. 
 
Q9 - 2024 (31 Jan Shift 2) 
A body of mass ' ?? ' is projected with a speed ' ?? ' making an angle of 45
°
 with the 
ground. The angular momentum of the body about the point of projection, at the highest 
point is expressed as 
 2mu
3
Xg
. The value of ' X
'
 is 
Q10 - 2024 (31 Jan Shift 2) 
Two identical spheres each of mass 2kg and radius 50cm are fixed at the ends of a light 
rod so that the separation between the centers is 150cm. Then, moment of inertia of the 
system about an axis perpendicular to the rod and passing through its middle point is 
?? 20
kgm
2
, where the value of x is 
Answer Key 
Q1 (2)  
Q2 (3)  
Q3 (16)  
Q4 (7)  
Q5 (10)  
Q6 (60)  
Q7 (250)  
Q8 (24)  
Q9 (8)  
Q10 (53) 
 
Solutions 
Q1 
T = m?? 2
l 
400 = 0.5?? 2
× 0.5 
?? = 40rad/s. 
Q2 
Only the translational kinetic energy of disc changes into gravitational potential energy. 
And rotational KE remains unchanged as there is no friction. 
1
2
?? ?? 2
=?? ?? ?? 
?? =
?? 2
2?? 
Q3 
 
?? =?? ?? 2
+?? ?? 2
+?? ( 2?? )
2
= 4?? ?? 2
= 4 × 1 × (2)
2
= 16
 
Q4 
In pure rolling work done by friction is zero. Hence potential energy is converted into 
kinetic energy. Since initially the ring and the sphere have same potential energy, finally 
they will have same kinetic energy too. 
? Ratio of kinetic energies = 1 
?
7
?? = 1??? = 7 
Q5