Answer
a. $3.3\times10^5J$
b. 93 mins
Work Step by Step
Use equation 14–2. One liter of water has a mass of 1 kg.
a. $Q=mc\Delta T=(1.0kg)(\frac{4186J}{kg\cdot C^{\circ}})(100^{\circ}C-20^{\circ}C)=3.3\times10^5J$
b. Power is the rate at which energy is used.
$$P=60\frac{J}{s}=\frac{3.349\times10^5J }{t}$$
Solve for t = 5582s, or about 93 minutes.
