Dangerous Goods Practice Test 2026 - Free Dangerous Goods Exam Practice Questions and Study Guide

To calculate the watt-hour rating of a battery, you can use the formula:

Watt-hours (Wh) = Amp-hours (Ah) × Voltage (V)

First, it's important to convert the battery rating from milliamp-hours (mAh) to amp-hours (Ah). Since 1,000 mAh equals 1 Ah, the battery's 3000 mAh rating can be converted as follows:

3000 mAh = 3000 / 1000 = 3 Ah

Now that we have the capacity of the battery in Amp-hours, we can use the formula by substituting the values:

Wh = 3 Ah × 5 V = 15 Wh

Thus, the watt-hour rating of the battery is 15 Wh. This calculation accounts for both the capacity of the battery and the voltage, allowing you to determine how much energy the battery can deliver over a period of time. The answer of 15 Wh reflects the effective energy storage capability of the battery at that voltage and capacity.