Physics-
General
Easy
Question
A uniform disc of radius R, specific gravity 3 and mass ' M ' is immersed in water and fixed at the top point 'p' on its rim as shown in the fig. If can rotate in the plane of the fig about the axis passing through ' P ' If the disc is displaced by a small angle 
from the vertical position what is net torque that acts on the disc about point P.
The correct answer is:
Related Questions to study
physics-
A uniform rod of length 2l and mass m is placed on fixed sphere and the rod is held horizontal. The rod is released from rest with one fourth of length on one side of sphere. The normal reaction of sphere on the rod as soon as rod is released is
A uniform rod of length 2l and mass m is placed on fixed sphere and the rod is held horizontal. The rod is released from rest with one fourth of length on one side of sphere. The normal reaction of sphere on the rod as soon as rod is released is
physics-General
physics-
A uniform rod of length 1 is pivoted at point A. It is struck by a horizontal force which delivers an impulse J at a distance x from point A as shown in fig, impulse delivered by pivot is zero if x is equal to
A uniform rod of length 1 is pivoted at point A. It is struck by a horizontal force which delivers an impulse J at a distance x from point A as shown in fig, impulse delivered by pivot is zero if x is equal to
physics-General
physics-
A rod AB of length 1 m is placed at the edge of a smooth table as shown in fig. It is hit horizontally at point B. If the displacement of centre of mass in 1 s is 
. The angular velocity of the rod is 
A rod AB of length 1 m is placed at the edge of a smooth table as shown in fig. It is hit horizontally at point B. If the displacement of centre of mass in 1 s is . The angular velocity of the rod is
physics-General
physics-
A small block of mass ' m ' is rigidly attached at ' P ' to a ring of mass ' 3 m ' and radius ' r '. The system is released from rest at 
and rolls without sliding. The angular acceleration of hoop just after releases is -
A small block of mass ' m ' is rigidly attached at ' P ' to a ring of mass ' 3 m ' and radius ' r '. The system is released from rest at and rolls without sliding. The angular acceleration of hoop just after releases is -
physics-General
physics-
A smooth horizontal tube of length l rotates about a vertical axis as shown. A particle placed at the extreme end of the tube is projected towards 0 with a velocity 
, while at the same time the tube rotates about the axis with constant angular speed 
. The path of the particle is given by
A smooth horizontal tube of length l rotates about a vertical axis as shown. A particle placed at the extreme end of the tube is projected towards 0 with a velocity , while at the same time the tube rotates about the axis with constant angular speed . The path of the particle is given by
physics-General
physics-
A disc of mass m and radius R moves in the x-y plane as shown in. The angular momentum of the disc about the origin O at the instant shown is
A disc of mass m and radius R moves in the x-y plane as shown in. The angular momentum of the disc about the origin O at the instant shown is
physics-General
physics-
Moment of inertia of a rectangular plate about an axis passing through P and perpendicular to the plate is I. Then moment of PQR about an axis perpendicular to the plane of the plate:
Moment of inertia of a rectangular plate about an axis passing through P and perpendicular to the plate is I. Then moment of PQR about an axis perpendicular to the plane of the plate:
physics-General
physics-
A square plate of edge a/2 is cut out from a uniform square plate of edge ' a ' as shown in figure. The mass of the remaining portion is M. The moment of inertia of the shaded portion about an axis passing through ' O ' (centre of the square of side (A) and perpendicular to plane of the plate is
A square plate of edge a/2 is cut out from a uniform square plate of edge ' a ' as shown in figure. The mass of the remaining portion is M. The moment of inertia of the shaded portion about an axis passing through ' O ' (centre of the square of side (A) and perpendicular to plane of the plate is
physics-General
physics-
The fig shows a uniform rod lying along the x-axis. The locus of all the points lying on the xy-plane, about which the moment of inertia of the rod is same as that about O is :
The fig shows a uniform rod lying along the x-axis. The locus of all the points lying on the xy-plane, about which the moment of inertia of the rod is same as that about O is :
physics-General
physics-
A thin rod of length 4l, mass 4 m is bent at the points as shown in the fig. What is the moment of inertia of the rod about the axis passing point O& perpendicular to the plane of the paper.
A thin rod of length 4l, mass 4 m is bent at the points as shown in the fig. What is the moment of inertia of the rod about the axis passing point O& perpendicular to the plane of the paper.
physics-General
physics-
Figure below shows the variation of the moment of inertia of a uniform rod about an axis normal to its length with the distance of the axis from the end of the rod. The moment of inertia of the rod about an axis passing through its centre and perpendicular to the its length is :
Figure below shows the variation of the moment of inertia of a uniform rod about an axis normal to its length with the distance of the axis from the end of the rod. The moment of inertia of the rod about an axis passing through its centre and perpendicular to the its length is :
physics-General
physics-
Two thin rods of mass 
and length l each are joined to form l shape as shown. The moment of inertia of rods about an axis passing through free end (O) of a rod and perpendicular to both the rods is:
Two thin rods of mass and length l each are joined to form l shape as shown. The moment of inertia of rods about an axis passing through free end (O) of a rod and perpendicular to both the rods is:
physics-General
physics-
A right triangular plate 
of mass is free to rotate in the vertical plane about a fixed horizontal axis through A. It is supported by a string such that the side AB is horizontal. The reaction at the support A is
A right triangular plate of mass is free to rotate in the vertical plane about a fixed horizontal axis through A. It is supported by a string such that the side AB is horizontal. The reaction at the support A is
physics-General
physics-
A cylinder of mass m suspended by two strings wrapped around the cylinder one near each end, the free ends of the strings being attached to hooks on the ceiling, such that the length of the cylinder is horizontal, From the position of rest, the cylinder is allowed to roll down as suspension strings unwind. Then calculate the time dependence of the instantaneous power developed by gravity
A cylinder of mass m suspended by two strings wrapped around the cylinder one near each end, the free ends of the strings being attached to hooks on the ceiling, such that the length of the cylinder is horizontal, From the position of rest, the cylinder is allowed to roll down as suspension strings unwind. Then calculate the time dependence of the instantaneous power developed by gravity
physics-General
physics-
A man pushes a cylinder of mass 
with the help of a plank of mass 
as shown. There is no slipping at any contact. The horizontal component of the force applied by the man is F. The acceleration of the plank
A man pushes a cylinder of mass with the help of a plank of mass as shown. There is no slipping at any contact. The horizontal component of the force applied by the man is F. The acceleration of the plank
physics-General
