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→Finding Current from Potential Difference and Resistance
====Finding Current from Potential Difference and Resistance====
{| class="wikitable"
| style="height:20px; width:300px; text-align:center;" |A [[Potential Difference|potential difference]] of 9.9V is placed across an 18 19 Ohm [[Electrical Resistor|resistor]]. Calculate the '''current''' flowing through the [[Electrical Resistor|resistor]] correct to two [[Significant Figures|significant figures]].
| style="height:20px; width:300px; text-align:center;" |A toaster has a [[Electrical Resistance|resistance]] of 27 Ohms is plugged into the [[Mains Electricity|mains]] which has a [[Potential Difference|potential difference]] of 230V. Calculate the current flowing through the toaster correct to two [[Significant Figures|significant figures]].
|-
V = 9.9V
R = 18Ω19Ω
| style="height:20px; width:300px; text-align:left;" |'''1. State the known quantities in correct [[unit]]s.'''
V = 230V
<math>I=\frac{V}{R}</math>
<math>I=\frac{9.9}{1819}</math>
<math>I=0.55A52105A</math>
<math>I\approx0.52A</math>
| style="height:20px; width:300px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers into the [[equation]] and [[Solve (Maths)|solve]].'''