Electric Current Physics Example 4

Follow the full solution, then compare it with the other examples linked below.

Example 4

medium
A phone charger delivers a steady current of 2.0 A2.0 \text{ A} for 30 minutes30 \text{ minutes}. How much total electric charge flows through the cable?

Solution

  1. 1
    Convert time: 30 min=30×60=1800 s30 \text{ min} = 30 \times 60 = 1800 \text{ s}.
  2. 2
    Use Q=ItQ = It: Q=2.0×1800=3600 CQ = 2.0 \times 1800 = 3600 \text{ C}

Answer

Q=3600 CQ = 3600 \text{ C}
Current is the rate of charge flow (I=Q/tI = Q/t). Rearranging gives Q=ItQ = It. Always convert time to seconds when current is in amperes.

About Electric Current

Electric current is the rate at which electric charge flows past a point in a circuit or conductor.

Learn more about Electric Current →

More Electric Current Examples

Example 1 easy

A charge of [formula] flows through a wire in [formula]. What is the electric current?

Example 2 medium

A current of [formula] flows through a lamp for [formula]. How much charge passes through the lamp?

Example 3 easy

How long does it take for [formula] of charge to flow through a circuit with a current of [formula]?

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