Lake erie contains roughly 4.00 ✕ 1011 m3 of water. (a) how much energy is required to raise the temperature of that volume of water from 17.8°c to 21.6°c? (assume the density of this water to be equal to that of water at 20°c and 1 atm.) j (b) how many years would it take to supply this amount of energy by using the 1,400-mw exhaust energy of an electric power plant? yr

Part a)

Part b)

Explanation:

Part a)

Energy required to raise the temperature of water from 17.8 degree C to 21.6 degree C is given by formula

here we know that

Here the volume of the water is given as

now the mass of water is

now the heat required is

Part b)

As we know that power is supplied at

so here we know

so here we have

float.

archimedes' principle

denser than water sinks in water.

denser than mercury would sink in it