Advertisements
Advertisements
Question
An electric immersion heater is rated 1250 W. Calculate the time in which it will heat 20 kg of water at 5°C to 65°C.
Advertisements
Solution
Power supplied by an electric heater (VI) = 1250 W
θ1 = Initial temperature = 5°C
m = Mass of water = 20 kg
θ2 = Final temperature = 65°C
c = specific heat capacity by heater = Heat gained by water ...(Law of calorimeter)
VIt = mc (θ2 - θ1) .....(Q = VI t)
1250 t = 20 × 4200 × 60 ....[(65°C - 5°C = 60°C)]
1250 t = 5040000
t = 40325 seconds
RELATED QUESTIONS
Water property of water makes it an effective coolant?
A heater of power P watt raises the temperature of m kg of a liquid by Δt K in time t s. Express
the specific heat capacity of liquid in terms of above data.
What is the unit of heat capacity in CGS system?
Define specific heat capacity.
Derive Meyer’s relation for an ideal gas.
Two uniform brass rods A and B of length land 2l and radii 2r and r respectively are heated to the same temperature. The ratio of the increase in the volume ofB to that of A is ____________.
To study energy exchange between hot and cold objects, the system of both objects is isolated from the environment by keeping them inside ______.
Specific heat capacity of a substance X is 1900 Jkg-1°C-1 means ______.
Two blocks P and Q of different metals having their mass in the ratio 2 : 1 are given same amount of heat. Their temperature rises by same amount. Compare their specific heat capacities.
