Q.

A solid sphere and a hollow cylinder roll up without slipping on the same inclined plane with the same initial speed v. The sphere and the cylinder reach up to maximum heights h1 and h2, respectively, above the initial level. The ratio h1:h2 is n10. The value of n is _____.      [2024]


Ans.

(7)

Energy conservation, Gain in P.E. = Loss in K.E.

12mv2+12Iω2=mgh

For pure rolling; v=ωR

12mv2+12Iv2R2=mgh

12v2(m+mK2R2)=mgh

mgh=12mv2(1+K2R2)h1+K2R2

h1h2=1+251+1=75×2=710

Hence, n=7