Electric Problem: Calculating Energy Used

Thread starter oct032007
Start date Mar 22, 2010
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Electric

AI Thread Summary

To calculate the energy used by a flashlight powered by two 1.5V batteries in series, the total voltage is 3.0V. The current draw is 1.00 mA, which is equivalent to 0.001 A. The flashlight is on for 2.0 minutes, or 120 seconds. Using the formula for energy (Energy = Voltage x Current x Time), the energy consumed can be calculated as 3.0V * 0.001A * 120s, resulting in 0.36 Joules. This approach effectively addresses the problem of calculating energy usage in electrical devices.

Mar 22, 2010

oct032007

Homework Statement

A flashlight, which uses two 1.5V batteries in series, is turned on for 2.0 minutes. If the current in the flashlight is 1.00 mA, how much energy is used?

Homework Equations

Not really sure.

The Attempt at a Solution

I am having a problem with this question.

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Mar 22, 2010

rl.bhat

Homework Helper

Energy used is V*I*t Joules.

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