WAEC - Physics (2013 - No. 19)
An electric heater has a resistance of 50\(\Omega\). When it is immersed in water and connected to mains source, it draws a current of 4.0A. Calculate the heat gained by the water if the heater is switched on for 2 minutes, assuming no heat losses to the surroundings
4200J
1600J
24000J
96000J
解释
Q = \(I^2RT\)
= \(4^2\) x 50 x 2 x 60
= 96000J
= \(4^2\) x 50 x 2 x 60
= 96000J