How Much Does It Cost to Run a Digital Clock for 34 Days?

Thread starter haleyscavone
Start date Dec 4, 2008

AI Thread Summary

To calculate the cost of running a digital clock for 34 days, first determine the current using Ohm's law, where current (I) equals voltage (V) divided by resistance (R). With a resistance of 11,000 ohms and a voltage of 114 volts, the current is approximately 0.01036 amps. The power consumed can be calculated using the formula P = V * I, resulting in about 1.18 watts. Over 34 days, the total energy consumption in kilowatt-hours is approximately 0.999 kWh, leading to a total cost of about $0.09 for operation. Understanding these calculations is essential for estimating the operational costs of electrical devices.

Dec 4, 2008

haleyscavone

A digital clock has an operating resistance of 11000 and is plugged into a 114-V outlet. Assume the clock obeys Ohm's law.

If the owner of the clock pays $0.09 per kWh, what does it cost to operate the clock for 34 days?

Where do I even begin?

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Dec 4, 2008

Borek

Mentor

What current goes through the clock?

How does power depend on the current and voltage?

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