Explanation:
Given:
mass of water = 500 g
Power = 1 KW
specific latent heat of vaporization of water = 2.26Mj/kg
To find:
time t =?
Step-to-step-explanation:
We have to find the time needed to evaporate all the water in the kettle.
The boiling point of water is 100°C.
Hence we have to find the time needed to boil water up to 100°C.
First, the heat required to boil water up to 100°C is given by:
Heat = mass × specific latent heat × temperature
= 500 × 2.26 × 100
= 113000 J
The power required to boil the cattle is 1 KW i.e. 1000 W.
We know that power is the ratio of energy & time.
P = H/t
1000 = 113000/t
t = 113 sec
t = 3 min 23 sec
Hence, the time needed to evaporate all the water in the kettle is 3 min 23 sec.
