Battery Life Calculator - How long will it power a circuit? mah

The video tutorial explains how to interpret the milliamp hour (mAh) rating of a battery, which indicates its capacity to provide current over time. It discusses factors affecting real-life battery performance, such as internal resistance, age, and temperature, which can reduce the expected lifespan. A formula is provided to estimate battery life by dividing the battery's capacity by the circuit's current demand, though actual performance may vary.

What does a 2500 mAh rating on a battery indicate?

• The battery can provide 2500 milliamps for one hour under ideal conditions.

• The battery can provide 2500 milliamps for two hours under ideal conditions.

• The battery can provide 125 milliamps for 20 hours under ideal conditions.

• The battery can provide 1250 milliamps for one hour under ideal conditions.

Which of the following factors does NOT affect the actual lifespan of a battery?

• The color of the battery casing

• The temperature at which the battery operates

• The age of the battery

• Chemical reactions within the battery

Why is it difficult to precisely calculate the lifespan of a battery?

• Because the battery's capacity is always changing

• Because the internal resistance remains constant

• Because the chemical reaction and internal resistance change as the battery discharges

• Because the battery's voltage is unpredictable

How can we estimate the lifespan of a battery?

• By dividing the battery's voltage by the circuit's resistance

• By multiplying the battery's capacity by the circuit's current

• By dividing the battery's capacity in mAh by the circuit's current in milliamps

• By adding the battery's capacity to the circuit's current

In the example given, what is the estimated battery life for a circuit with a demand of 19 milliamps and a battery capacity of 3000 mAh?

• 157 hours

• 1579 hours

• 157.29 hours

• 15729 hours