In series circuit, Req = R₁ + R₂ + R₃ + ···
In parallel circuit, [tex]\frac{1}{Req} = \frac{1}{R1} + \frac{1}{R2} + \frac{1}{R3} +...[/tex]
Q7.
total resistance in the upper branch = R₂ + R₃ = R₂ + 2
[tex]\frac{1}{Req} = \frac{1}{R2+R3} + \frac{1}{R1}[/tex]
[tex]\frac{1}{4} = \frac{1}{R2+2} +\frac{1}{6}[/tex]
R₂ + 2 = 12
R₂ = 10Ω
Q8.
[tex]\frac{1}{Req} = \frac{1}{R2+R3} + \frac{1}{R1}[/tex]
[tex]\frac{1}{Req} = \frac{1}{2+1} + \frac{1}{4}[/tex]
Req = 1.7Ω
