511. A hoop and disc have same mass and radius. Their rotational K.E are related by an equation______________?
A. K.E hoop = K.E disc
B. K.E hoop = 2K.E disc
C. K.E hoop = 1/2K.E disc
D. K.E hoop = 4K.E disc

512. The critical speed of an artificial satellite is_______________?
A. 8 Kms-1
B. 8.1 Kms-1
C. 7.9 Kms-1
D. 8 ms-1

513. Geostationary satellite completes one rotation around the earth in_______________?
A. 3 hours
B. 6 hours
C. 12 hours
D. 24 hours

514. The radius of geostationary orbit from the centre of the earth is nearly______________?
A. 42000km
B. 36000km
C. 24000 km
D. 18000 km

515. According to Einstein, the gravitational interaction is possible between_______________?
A. material objects only
B. material objects and electromagnetic radiation only
D. none of the above

516. One radian is equal to______________?
A. 67.3°
B. 57.3°
C. 87.3°
D. 60°

517. The period of a circular motion is given by_______________?
A. T = πv
B. T = πw.
C. T = 2πr
D. T = 2πr/v

518. The direction of the linear velocity of a body moving in a circle is______________?
A. along the axis of rotation
B. along the tangent
C. directed towards the centre
D. directed away from the centre

519. hen a body moves in a circle, the angle between its linear velocity and angular velocity is always_______________?
WA. 180°
B. 0°
C. 90°
D. 45°

520. The circumference subtends an angle________________?