A piece of ice falls from a hight h so that it melts completely. Only one quarter of the heat produced is absorbed by the ice and all energy of ice gets converted into heat during its fall. The value of h is : (Latent heat of ice is `3.4xx10^(5) j//kg` and `g=10N//kg`)

Options

A. 34 km
B. 544 km
C. 136 km
D. 68 km

Answer

C

Explanation

Useful workdone to convert ice into water
`=(1)/(4)mgh`
Heat required to convert ice water = mL
`:. (1)/(4)mgh =mL`
or `h=(4L)/(g) =(4xx3.4xx10^(5))/(10) =13.6xx10^(4)m =136 km`