The ratio of the radii of gyration of a circular disc to that of a circular ring, each of same mass and radius, around their respective axes is
√3 : √2
1 : √2
√2 : 1
√2 : √3
ABC is a triangular plate of uniform thickness. The sides are in the ratio shown in the figure. I AB – I BC and I CA are the moments of inertia of the plate about AB, BC and CA as axes respectively. Which one of the following relations is correct ?
I AB > IBC
I BC > I AC
I AB + I BC = ICA
I CA is maximum
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
5 I
3 I
6 I
4 I
Two bodies of mass 1 kg and 3 kg have position vectors respectively. The centre of mass of this system has a position vector
Four identical thin rods each of mass M and length l, form a square frame. Moment of inertia of this frame about an axis through the centre of the square and perpendicular to its plane is
4/3 Ml2
2/3 Ml2
13/3 Ml2
1/3 Ml2
A thin circular ring of mass M and radius R is rotating in a horizontal plane about an axis vertical to its plane with a constant angular velocity ω. If two objects each of mass m be attached gently to the opposite ends of a diameter of the ring, the ring will then rotate with an angular velocity
A weightless ladder 20 ft long rests against a frictionless wall at an angle of 60o from the horizontal. A 150 pound man is 4 ft from the top of the ladder . A horizontal force needed to keep it form slipping. Choose the correct magnitude of force from the following.?
17.3 pound
100 pound
120 pound
150 pound
Angular momentum :
Vector (axial )
Vector ( polar )
Scalar
None of these
Two racing cars of masses m and 4m are moving in circles of radii r and 2r respectively. If their speeds are such that each makes a complete circle in the same time. Then the ratio of the angular speeds of the first to the second car is
8: 1
4 : 1
2 :1
1 : 1
Consider a system of two particles having masses m1 and m2. If the particle of mass m1 is pushed towards the mass centre of particles through a distance d, by what distance would the particles of mass m2 move so as to keep the mass centre of the particles at the original position?
d