Help with #4 Physics Question???? I really need help guys!
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Answer: 5A
Method 1
For R₂, V=IR,
V₂ = 2.5×8
= 20 V
Since the voltage across each branch of the parallel circuit is the same, the voltage across R₂ is equal to that of R₃.
So, for R₃, V₃=20V
V=IR
20 = I × 4
I = 5A
Method 2
In parallel circuit, the ratio of the resistance in each branch are inversely proportional to the ratio of current in each branch.
[tex]\frac{R2}{R3} =\frac{I3}{I2} \\\frac{8}{4} =\frac{I3}{2.5} \\I3 =5A[/tex]