A rotating space heater used 1,400 joules of energy while heating a room. Of that total, 896 joules produced thermal energy, 181 joules produced kinetic energy, 203 joules produced light energy, and 120 joules produced sound energy. What is the space heater’s efficiency?(1 point)
Responses
64%
64%
56.25%
56.25%
156.25%
156.25%
36%
To find the efficiency of the space heater, we need to calculate the ratio of useful output energy to the total input energy.
The useful output energy is the sum of thermal energy, kinetic energy, light energy, and sound energy, which is 896J + 181J + 203J + 120J = 1,400J.
Therefore, the efficiency is (useful output energy / total input energy) x 100 = (1,400J / 1,400J) x 100 = 100%.
The space heater's efficiency is 100%.