(g) A 2 kW kettle containing 1.5 kg of water at 15°C is switched on for 5 minutes. i. How much heat energy is transferred? ii. What will be the temperature rise of the water? (Cwater = 4.2k] kg-1 K-') iii. What is the final temperature of the water?

[b] About how many joules of heat energy does it take to cook a pound of pasta? Use reasonable estimates of pasta cooking methods as well as the heat capacity of water. (It might be useful to know that the mass of a pound of pasta is about 0.45 kg, and that cooked pasta has twice the mass of uncooked pasta because it has absorbed its mass in water. Or it might not.)

(II) (a) How much energy is required to bring a 1.0-L pot ofwater at 20°C to 100°C? (b) For how long could this amountof energy run a 60-W lightbulb?

A pot containing 0.6 kg of water at 25 degrees celsius was accidentally left on the stove until it boiled dry. Calculate the heat energy required to (i) heat the water up to 100 degrees Celsius (ii) to convert the water to steam. (iii) if the stove has a useful power rating of 900W, how much time does it take for the pot to boil dry?[specific heat capacity of water = 4,200kg K; Specific latent heat of vaporization of water =2.3 multiply by 10 to the sixth power J kg]

(8) If 3×10° J heat energy is required to convert ice at -20°C completely into steam at 100°C at normal atmospheric pressure then calculate the mass of ice.

Occasionally, huge icebergs are found floating on the ocean’s currents. Suppose one such iceberg has a regular volume and is 120 km long, 35 km wide, and 230 m thick. (i)    How much heat would be required to melt this iceberg (assumed to be at 0°C) into liquid water at 0°C? (The density of ice is 917 kg/m3. The latent heat of fusion for ice is 33.5 x 104 J/kg.) (ii)   Assume the average annual energy consumption by a developed country in the past years was 9.3 x 1019 J. If this energy were delivered to the iceberg every year, how many years would it take before the ice is completely melted? (iii)  What will be the outcome(s) and possible implication(s) in (ii) if the time rate of the changes in average annual energy consumption is a positive number?

(II) Typical temperatures in the interior of the Earth and Sun are about 4000°C and 15 x 106 °C, respectively. (a) What are these temperatures in kelvins? (b) What percent error is made in each case if a person forgets to change °C to K?

(1b). A wood stove is used to heat a single room. The stove is cylindrical in shape, with a diameter of 24 cm and a length of 58 cm, and operates at a temperature of 350°F. If the temperature of the room is 60°F, and if the emissivity is 0.91, then Calculate, the amount of radiant energy delivered to the room by the stove each second (KW) O O D v

In a study of healthy young men[1], doing 20 pushups in 1 minute burned an amount of energy per kg that for a 70.0-kg man corresponds to 8.06 calories (kcal). How much would a 70.0-kg man’s temperature rise if he did notlose any heat during that time?