Mathematical and Physical Journal
for High Schools
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Problem P. 4819. (March 2016)

P. 4819. Half a litre of water is boiled by means of an immersion heater, rated at 500 W. How long does it take to increase the temperature of the 0.5 litres of water from \(\displaystyle 20~^\circ\)C to its boiling point, if the efficiency of heating is 80%? What may the reason be for the 20% loss of energy if the heat released by the immersion heater is totally absorbed by the water?

(3 pont)

Deadline expired on April 11, 2016.


100 students sent a solution.
3 points:68 students.
2 points:25 students.
1 point:5 students.
0 point:2 students.

Problems in Physics of KöMaL, March 2016