Question

A coffee maker has a power rating of 1.4 kW. How much energy will this coffee maker transfer every second?

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Answer 1

A coffee maker rated at 1.4 kW will transfer 1400 joules of energy every second it is in operation, as power is the rate of energy transfer and 1 watt equals 1 joule per second.

Step-by-step explanation:

A coffee maker with a power rating of 1.4 kW (which is equivalent to 1400 watts) will transfer 1400 joules of energy every second. Power is defined as the rate at which energy is transferred or converted. Since power is measured in watts and one watt is equal to one joule per second, a 1.4 kW appliance will use 1.4 kW × 1000 W/kW = 1400 W, hence it will transfer 1400 J every second it operates.

Moreover, understanding the power rating is crucial for estimating energy consumption and cost. For instance, if the coffee maker operates for one hour, it would consume 1400 watts per second multiplied by 3600 seconds in an hour, resulting in a total energy consumption of 5,040,000 joules (or 1400 watt-hours). This knowledge helps users gauge the electrical demands of the appliance and make informed decisions about energy usage and efficiency.

Answer 2

The power rating of the coffee maker is 1.4 kW, which means that it uses 1.4 kilowatts of power when it is in operation. To find out how much energy it will transfer every second, we can use the formula:

Energy transferred = Power × Time

Since we want to know the energy transferred every second, we can set the time to 1 second. Therefore:

Energy transferred per second = Power × 1 second

Energy transferred per second = 1.4 kW × 1 second

We can simplify this by converting the unit of power from kilowatts to watts:

Energy transferred per second = 1,400 watts × 1 second

Energy transferred per second = 1,400 joules

Therefore, the coffee maker will transfer 1,400 joules of energy every second.