A fryer consumes an amount of electrical energy of 4400 kJ in 30 minutes. In 5 minutes, it provides a quantity of thermal energy of 0.125 kWh. Calculate the efficiency of the device.

Answer 1

To calculate the efficiency of the fryer, we need to find the ratio of the useful output energy (thermal energy) to the energy input (electrical energy).

First, let's convert the thermal energy provided in 5 minutes to kilojoules (kJ):
0.125 kWh = 0.125 * 1000 Wh = 125 Wh
1 Wh = 3600 J
125 Wh = 125 * 3600 J = 450000 J = 450 kJ

So, in 5 minutes, the fryer provides a thermal energy of 450 kJ.

Now we can calculate the efficiency:
Efficiency = (Useful Output Energy / Energy Input) * 100%
= (450 kJ / 4400 kJ) * 100%
= (0.1023) * 100%
= 10.23%

Therefore, the efficiency of the fryer is approximately 10.23%.