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% 36% 36% 156.25% 156.25%
To find the efficiency of the space heater, we need to compare the useful output energy (thermal energy) to the total input energy (1400 joules).
Efficiency = (Useful output energy ÷ Total input energy) x 100
Useful output energy = 896 joules
Total input energy = 1400 joules
Efficiency = (896 joules ÷ 1400 joules) x 100
= (0.64) x 100
= 64%
Therefore, the space heater’s efficiency is 64%.