When you put 250 g of water (20o C) in the microwave for 2 minutes, the...
When you put 250 g of water (20o C) in the microwave for 2 minutes, the water's temperature rises to 50o C. What was the power that the microwave delivers to the water during those 2 minutes?
Homework Answers
The temperature of the water rises because energy is delivered to it in the form of heat, and once we know how much energy was absorbed by the water, power is just energy over time. The equation that relates the heat exchange with the temperature difference is the following:
Where Q is the heat energy delivered by the oven, m is the mass of water, C is the heat capacity of water ( it's 1 cal = 4,184 J per gram and per degree) and delta T is the rise in temperature of the water:
2 minutes is 120 seconds in SI units, so power in Watts will be:
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