In summer, Kamal decides to take a bath at noon. Temperature of the water in overhead tank is `45^(@)C` so he decides to mix ince from refrigerator. The temperature of the ice in refrigerator. The temperature of the ice in refrigerator is `10^(@)C`. How much ice will be needed to prepare 20 kg of water at `25^(@)C` for bath? (Assume no loss to surrounding latent heat of fusion of ice `=80cal//gm`, specific heat of ice `=0.5cal//gm^(@)C`

Options

A. `400//115kg`
B. `40//13kg`
C. `40//11kg`
D. `400//135`kg

Answer

B

Explanation

if `m` kg ice is required then
`(20-m)xx1(45-25)=mxx(1)/(2)xx(0-(-10)+mxx80+mxx1(25-0)`
`(20-m)xx20=mxx110`
`m=(400)/(130)=(40)/(13)kg`