Two circular discs `A` and `B` of equal masses and thicknesses. But are made of metals with densities `d_A and d_B (d_A gt d_B)`. If their moments of inertia about an axis passing through the centre and normal to the circular faces be `I_A and I_B`, then.A. `I_A = I_B`B. `I_A gt I_B`C. `I_A lt I_B`D. `I_A ge I_B`

Two circular discs `A` and `B` of equal masses and thicknesses. But ar

1.	Two circular discs `A` and `B` of equal masses and thicknesses. But are made of metals with densities `d_A and d_B (d_A gt d_B)`. If their moments of inertia about an axis passing through the centre and normal to the circular faces be `I_A and I_B`, then.A. `I_A = I_B`B. `I_A gt I_B`C. `I_A lt I_B`D. `I_A ge I_B`
Answer» Correct Answer - C ( c) mass = volume `xx` density `rArr M = (pi R^2 t)d`…(1) where `t` is thickness `I = (MR^2)/(2)` …(2) From (1) and (2), we get : `I = (M^2)/(2 pi dt) rArr I prop (1)/(d) rArr I_A lt I_B`.

Discussion

No Comment Found

Related InterviewSolutions

A tight rope walker in a circus holds a long flexible pole to help stay balanced on the rope. Honding the pole horizontally and perpendicular to the rope helds the performer. .A. by lowering the overall centre of gravityB. by increasing the rotation inertiaC. in the ability to adust the centre gravity to the be over the ropeD. in achieving the centre of gravity to be under the rope.
A sphere of mass `M` and radius `R` is attached by a light of length `1` to a point `P`. The sphere rolls without slipping on a circular track as shown. It is released from the horizontal position. The angular momentum of the system about `P` when the rod becomes vertical is : .A. `M sqrt((10)/(7)) gl[l + R]`B. `M sqrt((10)/(7)) gl[ l + (2)/(5) R]`C. `M sqrt((10)/(7)) gl [l +(7)/(5) R]`D. none of the above
A solid sphere rolling on a rough horizontal surface. Acceleration of contact point is zero. A solid sphere can roll on the smooth surface.A. If both assertion and reason are true and reason is the true explanation of assertion.B. If both assertion and reason are reason are true but reason is not the correct explanation of assertion.C. If assertion is true but reason is falseD. If both assertion and reason are false.
A sphere is performing pure rolling on a rough horizontal surface with constant angular velocity. Frictional force acting on the sphere is zero. Velocity of contact point is zero.A. If both assertion and reason are true and reason is the correct explanation of assertion.B. If both assertion and reason are reason are true but reason is not the correct explanation of assertion.C. If assertion is true but reason is falseD. If both assertion and reason are false.
A sphere is performing pure rolling on a rough horizontal surface with constant angular velocity. Frictional force acting on the sphere is zero. Velocity of contact point is zero.A. Statement-1 is True, Statement-2 is Ture , Statement -2 is a correct explanation for statement -1.B. Statement-1 is True, Statement-2 is True , Statement-2 is NOT a correct explanation fro Statement -1.C. Statement-1 is True, Statement-2 is False.D. Statement-1 is False, Statement-2 is True.
A mass M moving with a constant velocity parlale to the X-axis. Its angular momentum with respect to the originA. is zeroB. remains constantC. goes on increasingD. goes on decreasing
A solid sphere is rotating in free space. If the radius of the sphere is increased keeping mass same which one of the following wil not be affected?A. Moment of inertiaB. Angular momentumC. Angular velocityD. Rotational kinetic energy
A circular platform is mounted on a vertical frictionless axle. Its radius is `r = 2 m` and its moment of inertia`I = 200 kg m^2`. It is initially at rest. A `70 kg` man stands on the edge of the platform and begins to walk along the edge at speed `v_0 = 1 m s^-1` relative to the ground. The angular velocity of the platform is.A. `1.2 rad s^-1`B. `0.4 rad s^-1`C. `0.7 rad s^-1`D. `2 rad s^-1`
A ring of radius `R` is rotating with an angular speed `omega_0` about a horizontal axis. It is placed on a rough horizontal table. The coefficient of kinetic friction is `mu_k`. The time after it starts rolling is.A. `(omega_0 mu_k R)/(2 g)`B. `(omega_0 g)/(2 mu_k R)`C. `(2 omega_0 R)/(mu_k g)`D. `(omega_0 R)/(2 mu_k g)`]
Two bodies `A and B` initially at rest are attrached towards each other due to gravitation. Given that `A` is much heavier. Than `B`. Which of the followings correctly describes the relative motion of the centre of mass of the bodies ?A. it moves towards `A`B. it moves towards `B`C. it moves perpendicular to the line joining the particlesD. it remains at rest.

Discussion

No Comment Found

Related InterviewSolutions

Reply to Comment