# 546 - Physics Questions Answers

Joshi sir comment Sir tell how to write time period eq for this question

In a gravity free space a small ball is placed at the centre of a box of the same mass. The ball and the box both are moving with velocity u towards a fixed wall. Assume all collisions are perfectly elastic.

A) How many collisions are possible?

B) find velocities of the box and the ball and the position of the ball relative to the box after all possible collisions.

pls solve question 8

. Dear Sir kindly help solve this question

A point source of light is placed at the centre of curvature

of a hemispherical surface. The radius of curvature is r

and the inner surface is completely reflecting. Find the

force on the hemisphere due to the light falling on it if

the source emits a power W. Sir this is figure given in question. Question: Electric field lines of portion of an electric field that is symmetrical with respect to rotation about y-axis are show in the figure. A charge particle stays in equilibrium at point (0,10). If modulus of charge of the particle is changed gradually till it shifts to another equilibrium position (0,0),estimate fractional change in the charge modulus.                                                      Options : A) 1/3 B)2/3 C)1/9 D)8/9

Dear Sir kindly help provide the correct approach and solution to solve this 2016 iit jee advanced rotational question.