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Electromagnetism Challenge #1 — Ohm's Law

Current through
a resistor.

Electromagnetism Easy

Problem

A 48 Ω resistor is connected across the terminals of a 12 V battery. Calculate the current flowing through the resistor.

  • Voltage\( V = 12\ \mathrm{V} \)
  • Resistance\( R = 48\ \Omega \)
  • Answer inamperes
Assume the battery has no internal resistance.
Hint: Ohm’s law ties the three together: \( V = IR \). Rearrange it so the current stands alone on one side.
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