ICS Part 1 Physics English Medium Chapter 5 Online Short Questions Test with Answers

Question # 1

Ans 1: The direction of angular momentum along the axis of rotation remains fixed. This is due to the fact that the axis of rotation of an object will not change its orientation unless an external torque causes it to do so .

Question # 2

Question # 3

Question # 4

Question # 5

Ans 1: The property of the body to resist any change in its state of rest or uniform angular velocity is called moment of inertia. For a point mass 'm'situated at a distance 'r' from the axis of rotation , the moment of inertia 'I' is given by ; I=mr²
Significance;
Moment of inertia plays the same role in angular motion as that of mass plays in linear motion. It is also called measure of rotational inertia in angular motion.Moment of inertia determines the angular acceleration while mass determines the linear acceleration.

Question # 6

Ans 1: Adhesive force between mud and tire is weal. When the mud files off the tyre of a moving bicycle, it always files along the tangent to the tyre. Because linear velocity is always tangent to the circle.

Question # 7

Ans 1: It states that
"Grasp the axis of rotation in right hand with the fingers curling in the direction of rotation , then the erect thumb will give the direction of angular velocity and angular momentum"

Question # 8

Ans 1: The moment of inertia is I =mr²
^{So it depends upon the mass of the body and its distance from the axis of rotation.}

Question # 9

Ans 1: Artificial gravity is the gravity like effect produced in an orbiting spaceship to overcome weightlessness.To create artificial gravity the spaceship is set into rotation around its own axis. The astronaut then is presses towards the outer rim and exerts a force on the floor of the spaceship in much the same way as on the earth.

Question # 10

Ans 1: Banked tracks are needed because friction alone cannot provide energy for centripetal force.
If the road is banked, so that the outer edge is above the inner edge, then a portion of the normal force from the road on the tyre points towards the center of the track; this fraction of the normal force can provide enough centripetal force to keep the car moving in a circle.