Which formula can be used for cost calculation related to electrical power?

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The formula that relates to cost calculation for electrical power involves calculating the total cost based on power usage and time. To determine the cost of running an electrical device, you first need to calculate the energy consumption, usually measured in kilowatt-hours (kWh). This is done by multiplying the power rating of the device (in kilowatts) by the operating time (in hours). Once you have the energy consumed, multiplying this by the cost per kilowatt-hour gives you the total cost.

For example, if a device uses 2 kW and operates for 3 hours, the energy used would be 2 kW x 3 h = 6 kWh. If the electricity cost is $0.20 per kWh, then the total cost would be 6 kWh x $0.20 = $1.20. Thus, the formula in this context focuses on how energy usage over time translates into a monetary cost.

The other options do not pertain to cost calculations for electrical power in the same direct manner:

  • The first option relates to Ohm’s Law, which deals with the relationship between voltage, current, and resistance.

  • The third option concerns efficiency, which is a measure of how well input energy is converted

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