A student uses an electric heater to raise the temperature of a sample of oil.
The student obtains the following data:
- Energy input to the heater: 18 000 J18\,000\text{ J}18000 J
- Increase in thermal energy store of the oil: 13 500 J13\,500\text{ J}13500 J
a.[2]
Use this data to calculate the efficiency of the heater.
b.[3]
The heater is used for 666 minutes. Calculate the power of the heater. Use the equation: energy transferred=power×time\text{energy transferred} = \text{power} \times \text{time}energy transferred=power×time
c.[4]
Explain how the student uses the equipment shown to obtain the data. In your answer you should:
- Include how any extra equipment is used.
- Explain how the quantities are calculated.