6 Replies
@Gyro Gearloose
Note for OP
+solved @user1 @user2... to close the thread when your doubt is solved. Mention the users who helped you solve the doubt. This will be added to their stats.@Gyro Gearloose any inputs?
ye to Adv ke PYQ jaisa hai
and ye mujhse tab bhi nahi bana tha
i think i have some idea but it just never worked
the problem i was running into was defining the potential for the extra mass of A around B
and i still get this problem weow ok
btw what about the q? Solution is given here, right?
This is a bit calculative but: densities of planets a and b are in the ratio 1:2. After the radius is halved the mass of a becomes m/8 if original mass was m. Similarly, the deposition gives B a new radius which would be (15^1/3)/2 times the initial radius, will its mass would be (2+7/8)m=23/8m. Now the ratio of escape velocities is ratio of sqrt(M/R); so the required ratio is sqrt((m/8)/(23m/8).(1/2)/(15^(1/3)/2) which gives the required answer as 23=10n.