Moment of inertia of an object does not depend upon _Ĭlarification: Moment of inertia does not depend on the angular velocity of the object but depends on all factors given in other options.ĩ. Analogue of mass in rotational motion is _Ĭlarification: Analogue of mass in rotational motion is the angular momentumĨ. To conserve angular momentum, his angular speed increases.ħ. If a person standing on a rotating disc stretches out his hands, the angular speed will _Ĭlarification: As the person stretches out his hands, his moment of inertia increases.
If an external force is present, then the velocity of the centre of mass will not remain constant. Statement 2: The linear momentum of the isolated system remains constant.Ī) Statements 1 and 2 are true and statement 2 is the correct explanation of statement 1ī) Statement one and two are true and statement2 is not the correct explanation of statement1Ĭ) Statement 1 is true, statement 2 is falseĭ) Statement 2 is true, statement 1 is falseĬlarification: The absence of external torque does not ensure the absence of external force. Statement 1: If there is no external torque on the body about its centre of mass, then the velocity of the centre of mass remains constant. Hence only linear momentum of the system does not change in time.ĥ. Also, net force is 0 does not mean net torque is 0. There may be external forces acting due to which kinetic energy or potential energy or both may change. If the resultant of all the external forces acting on a system of particles is 0, then from an inertial frame, one can surely say that _Ī) Linear momentum of the system does not change in timeī) Kinetic energy of the system does not change in timeĬ) Angular momentum of the system does not change in timeĭ) Potential energy of the system does not change in timeĬlarification: According to the law of conservation of linear momentum if external force is 0 then the linear momentum of the system does not change in time. Hence the angular momentum is conserved about the centre of the circle.Ĥ. Torque due to such a force about the centre is zero. About which point on the plane of the circle, will the angular momentum of the particles remain conserved?Ĭlarification: In uniform circular motion, centripetal force acts towards the centre. A particles undergoes uniform circular motion.
Its angular momentum with respect to the origin _Ĭlarification: Angular momentum = Mass of momentumĪs the particle moves, m, v and h all remain unchanged.ģ. A mass m is moving with a constant velocity along a line parallel to the x-axis, away from the origin. Hence the instantaneous speed of the point of contact is zero.Ģ. The instantaneous speed of the point of contact during rolling is zero.Ĭlarification: A rolling body can be imagined to be rolling about an axis passing through the point of contact of the body and the ground. The result is valid for both a horizontal and a vertical axis through the centroid, and therefore is also valid for an axis with arbitrary direction that passes through the origin.Engineering Physics Questions and Answers for Aptitude test focuses on “Moment of Inertia and its Significance”.ġ.