The number of molecules in a drop of water (0.0018 ml) at room temperature is

Answer

A, C

Explanation

Here `m == 0.5m^(2) = 500L = 500kg`
So the heat liberated during the water changes`20^(@)C to 5^(@)C`
`= 500 xx 4200 xx 15`[Delta theta = 20- 5= 15]`
`= 500 xx 4200 xx 15`
`= 75 xx 420 xx 1000`
`= 31500 xx 1000`
Let the height = h`
The required work
`= mgh = 10 xx 10 xx h= 100h`
But,`100h = 315000m`
`rArr h = 31500 m = 315km`