One end of a themally insulated copper rod of length `1 m` long and of `10 cm^(2)` in X-section is immersed in boiling water `(100^(@)C)` and the other in ice `(0^(@)C)` . If `K_(Cu) = 0.92 cal//cm.//s//.^(@)C` and `L_(ice) = 80 cal//g`, the ice that will melt per minute is

Options

A. `5.9 g`
B. `6.9 g`
C. `8.4 g`
D. `9.2 g`

Answer

B

Explanation

(2) `i = (Delta Q)/(Delta) = (KA Delta theta)/(L)`
`(m L_(ice))/(60) = (KA Delta theta)/(L)`
`(m xx 80)/(60) = (0.92 xx 10 xx (100 - 9))/(100)`
`m = 6.9 g`