How much energy is transferred to an electric kettle that is rated at 3 kilowatts if it is on for three minutes?
To solve the problem, we can use the formula:
Energy = Power x Time
where Power is the rating of the electric kettle in kilowatts (kW) and Time is the duration of its operation in minutes.
In this case:
Power = 3 kW
Time = 3 minutes
Substituting these values into the formula, we get:
Energy = 3 kW x 3 minutes
Energy = 9 kilowatt-minutes (kWmin)
Note that this is not the same as kilowatt-hours (kWh), which is a more commonly used unit of energy in household electricity bills. To convert kWmin to kWh, we need to divide by 60 (the number of minutes in an hour), which gives:
Energy = 9 kWmin ÷ 60 = 0.15 kilowatt-hours (kWh)
Therefore, the amount of energy transferred to the electric kettle in three minutes of operation is 9 kWmin or 0.15 kWh.
To determine the amount of energy transferred to an electric kettle, you can use the formula:
Energy (in kilowatt-hours) = Power (in kilowatts) x Time (in hours)
Since the given time is in minutes, it needs to be converted to hours. There are 60 minutes in an hour, so 3 minutes is equal to 3/60 = 0.05 hours.
Now, we can substitute the values into the formula:
Energy = 3 kilowatts x 0.05 hours
Energy = 0.15 kilowatt-hours
Therefore, the electric kettle will transfer 0.15 kilowatt-hours of energy if it is on for three minutes.