Discussion Forum



1)

Consider a disc rotating in the horizontal plane with a constant angular speed $\omega$ about its centre O. The disc has a shaded region on one side of the diameter and an unshaded region on one the other side as shown in the figure. When the disc is in the orientation as shown, two pebbles P and Q are simultaneously projected at an angle towards R. The velocity of the projection is in the y-z plane
and is the same for both pebbles with respect to the disc. Assume that (i) they land back on the disc before the disc has completed $\frac{1}{8}$ rotation,(ii) their  range  is less than half the disc radius, and (iii) $\omega$  remains constant throughout Then,

 23112021445_u8.PNG


A) P lands in the shaded region and Q in the unshaded region

B) P lands in the unshaded region and Q in the shaded region

C) both P and Q land in the unshaded region

D) both P and Q land in the shaded region

Answer:

Option *

Explanation:

The language of the question is not very clear. For example, the disc is rotating. Its different Points have different velocities. The relative velocity of pebble
with respect to which point, it is not clear. Further, actual initial positions of P and Q are also not given