A ship of mass kg initially at rest, is pulled by a force of through a distance of 3 m. Assuming that the resistance due to water is negligible, the speed of the ship is
1
1.5 m/s
2
60 m/s
3
0.1m/s
4
5 m/s
Official Solution
Correct Option: (3)
= 0.1 m/s
02
PYQ 1986
easy
physicsID: jee-adva
A reference frame attached to the earth
1
is an inertial frame by definition
2
cannot be an inertial frame because the earth is revolving round the sun
3
is an inertial frame because Newton?s laws are applicable in this frame
4
cannot be an inertial frame because the earth is rotating about its own axis
Official Solution
Correct Option: (4)
A rotating/revolving frame is accelerating and hence non-inertial. Therefore, correct options are (b) and (d).
03
PYQ 1986
medium
physicsID: jee-adva
A simple pendulum of length L and mass (bob) M is oscillating in a plane about a vertical line between angular limits- and For an angular displacement , the tension in the string and the velocity of the bob are T and v respectively. The following relations hold good under the above conditions
1
2
3
The magnitude of the tangential acceleration of the bob
4
Official Solution
Correct Option: (3)
Motion of pendulum is the part of a circular motion. In circular motion, it is better to resolve the forces in two perpendicular directions. First along radius (towards centre) and second along tangential. Along radius net force should be equal to and along tangent it should be equal to where is the tangential acceleration in the figure.
and or Correct options are (b) and (c).
04
PYQ 1992
easy
physicsID: jee-adva
A car is moving in a circular horizontal track of radius with a constant speed of . A plumb bob is suspended from the roof of the car by a light rigid rod. The angle made by the rod with the vertical is
1
zero
2
3
4
Official Solution
Correct Option: (3)
FBD of bob is T sin and T cos = mg
tan or
05
PYQ 1994
medium
physicsID: jee-adva
During paddling of a bicycle, the force of friction exerted by the ground on the two wheels is such that it acts
1
in the backward direction on the front wheel and in the forward direction on the rear wheel
2
in the forward direction on the front wheel and in the backward direction on the rear wheel
3
in the backward direction on both the front and the rear wheels
4
in the forward direction on both the front and the rear wheels
Official Solution
Correct Option: (1)
In the backward direction on the front wheel and in the forward direction on the rear wheel because during padding, its rear wheel moves in forward direction but the point where wheel touches the ground is in backward direction so friction will be in the forward direction so friction will be in the forward direction in the rear wheel but as the front wheel is not getting any torque so it will be stationary and the forces that causes the rotation is only frictional force.
06
PYQ 2001
medium
physicsID: jee-adva
A string of negligible mass going over a clamped pulley of mass supports a block of mass as shown in the figure. The force on the pulley by the clamp is given by
1
2
3
4
Official Solution
Correct Option: (4)
Weight of the pulley acts downwards. Weight of the block acts downwards. Total downward force
07
PYQ 2002
medium
physicsID: jee-adva
A long horizontal rod has a bead which can slide along its length and is initially placed at a distance L from one end A of the rod. The rod is set in angular motion about A with a constant angular acceleration . If the coefficient of friction between the rod and bead is , and gravity is neglected, then the time after which the bead starts slipping is
1
2
3
4
infinitesimal
Official Solution
Correct Option: (1)
Tangential force of the bead will be given by the normal reaction (N), while centripetal force is provided by friction . The bead starts sliding when the centripetal force is just equal to the limiting friction. Therefore,
Limiting value of friction
Angular velocity at time t is Centripetal force at time t will be
Equating Eqs. (i) and (ii), we get
For the bead starts sliding. In the figure, is perpendicular to the paper inwards.
08
PYQ 2007
medium
physicsID: jee-adva
Two particles of mass each are tied at the ends of a light string of length . The whole system is kept on a frictionless horizontal surface with the string held tight so that each mass is at a distance from the centre (as shown in the figure). Now, the mid-point of the string is pulled vertically upwards with a small but constant force . As a result, the particles move towards each other on the surface. The magnitude of acceleration, when the separation between them becomes is
1
2
3
4
Official Solution
Correct Option: (2)
The arrangement is shown in the figure. The separation between the two masses is . Each mass will move in the horizontal direction as shown in the figure. Let the tension in the string be . The forces acting at point and on one of the masses are shown in the figure.
Net force at point must equal zero. Also, for the mass ,
and . Equations (i) and (iii) give
09
PYQ 2010
medium
physicsID: jee-adva
block of mass is on an inclined plane of angle . The coefficient of friction between the block and the plane is and tan The block is held stationary by applying a force parallel to the plane. The direction of force pointing up the plane is taken to be positive. As is varied from to , the frictional force versus graph will look like
1
2
3
4
Official Solution
Correct Option: (1)
From of block, or
As varies from to , varies from + to . This value of friction is always less than or equal to in magnitude.
10
PYQ 2011
medium
physicsID: jee-adva
A ball of mass (m) 0.5 kg is attached to the end of a string having length (l) 0.5 m. The ball is rotated on a horizontal circular path about vertical axis. The maximum tension that the string can bear is 324 N. The maximum possible value of angular velocity of ball (in rad/s) is
1
9
2
18
3
27
4
36
Official Solution
Correct Option: (4)
component will cancel . component will provide necessary centripetal force to the ball towards centre or
or
Correct option is (d)
11
PYQ 2022
easy
physicsID: jee-adva
A solid sphere of mass and radius rolls without slipping on a fixed inclined plane with an angle of inclination from the horizontal .Two forces of magnitude each, parallel to the incline, act on the sphere, both at distance from the center of the sphere, as shown in the figure. The acceleration of the sphere down the plane is ____ (Take )
Official Solution
Correct Option: (1)
Solid sphere 1kg, 1m
About COM
Hence,the acceleration of the sphere down the plane is 2.86 ms-2.
12
PYQ 2023
medium
physicsID: jee-adva
A person of height 1.6 m is walking away from a lamp post of height 4 m along a straight line on the horizontal ground. The lamp post and the person are always vertical. If the speed of the person is 60 cm/sec, then find the speed of tip point of its shadow with respect to the person in cm/sec.
Official Solution
Correct Option: (1)
13
PYQ 2023
easy
physicsID: jee-adva
A particle of mass m is moving such that its velocity at a point (x,y) is given by v = α (y + 2x ), where α is a non-zero constant. What is the resultant force acting on the particle?
1
F = mα (y + 2x )
2
F = mα (x + 2y )
3
F = 2mα (y + 2x )
4
F = 2mα (x + y )
Official Solution
Correct Option: (4)
The correct answer is (D) F = 2mα (x + y )
=
=
14
PYQ 2023
medium
physicsID: jee-adva
A person of height 1.6 m is walking away from a lamp post of height 4 m along a straight line on the horizontal ground. The lamp post and the person are always vertical. If the speed of the person is 60 cm/sec, then find the speed of tip point of its shadow with respect to the person in cm/sec.