An office worker uses an immersion heater to warm 237 g of water in a light, covered, insulated cup from 20°c to 100°c in 6.00 minutes. the heater is a nichrome resistance wire connected to a 120-v power supply. assume that the wire is at 100°c throughout the 6.00-min time interval. (a) calculate the average power required to warm the water to 100°c in 6.00 min. (the specific heat of water is 4186 j/kg · °c.)

No matter what energy transformation we discuss, we know that no energy transfer is 100% efficient. you are about to enter a bicycle rave. you have trained extensively and eaten well to maximize your energy input throughout the bicycle race. you know that some of your kinetic energy will become wasted energy in the form of heat. what is the source of the heat energy and how can you minimize it to maximize the efficiency of your performance in the race? a) you are the source of the heat energy. you can minimize the heat energy but selecting the appropriate clothes to wear. b) air resistance is the source of he heat energy. you can minimize the air resistance by your position while riding the bicycle. c) friction is the source of the heat energy. you can minimize the friction by lubricating all appropriate parts and keeping the tires well inflated. d) kinetic energy is the source of the heat energy. you can reduce the production of heat energy but minimizing the energy you expend to race on the bicycle.