A body rolls down an inclined plane without slipping. The fraction of total energy associated with its rotation will be
Where k is radius of gyration of the body about an axis passing through centre of mass and R is the radius of the body.
In the following figure, a weight W is attached to a string wrapped round a solid cylinder of mass M mounted on a frictionless horizontal axle at O.
If the weight starts from rest and falls a distance h, then its speed at that instant is
1. Proportional to \(\text R\)
2. Proportional to \(1 \over R\)
3. Proportional to \(1 \over R^2\)
4. Independent of \(\text R\)
Moment of inertia of a uniform circular disc about a diameter is I. Its moment of inertia about an axis perpendicular to its plane and passing through a point on its rim will be
1. 5 I
2. 3 I
3. 6 I
4. 4 I
A disc and a solid sphere of the same radius but different masses roll off on two inclined planes of the same altitude and length. Which one of the two objects gets to the bottom of the plane first?
1. Disk
2. Sphere
3. Both reach at the same time
4. Depends on their masses
A particle of mass \(m\) moves in the\(XY\) plane with a velocity of \(v\) along the straight line \(AB.\) If the angular momentum of the particle about the origin \(O\) is \(L_A\) when it is at \(A\) and \(L_B\) when it is at \(B,\) then:
1. | \(L_A>L_B\) |
2. | \(L_A=L_B\) |
3. | The relationship between \(L_A\) and \(L_B\) depends upon the slope of the line \(AB.\) |
4. | \(L_A<L_B\) |
If a force acts on a body at a point away from the centre-of-mass, then:
1. | Linear acceleration changes |
2. | Angular acceleration changes |
3. | Both change |
4. | None of these |
1. | \(\dfrac{7}{3}~\text{m}\) | 2. | \(\dfrac{10}{7}~\text{m}\) |
3. | \(\dfrac{12}{7}~\text{m}\) | 4. | \(\dfrac{9}{7}~\text{m}\) |
A cord is wound round the circumference of wheel of radius r. The axis of the wheel is horizotal and moment of inertia about it is I. A weight mg is attached to the end of the cord and falls from rest. After falling through a distance h, the angular velocity of the wheel will be
1.
2.
3.
4.
A body falling vertically downward under gravity breaks into two parts of unequal masses. The center of mass of the parts taken together shifts horizontally towards
1. heavier piece
2. lighter piece
3. does not shift horizontally
4. depends on the vertical velocity at the time of breaking
A solid cylinder and a solid sphere, both having the same mass and radius, are released from a rough inclined plane. Both roll without slipping. Then,
1. the force of friction that acts on the two is the same
2. the force of friction is greater in the case of a sphere than in a cylinder
3. the force of friction is greater in the case of a cylinder than in a sphere
4. the force of friction will depend on the nature of the surface of the body that is moving and that of the inclined surface and is independent of the shape and size of the moving body