Question

For this circuit, what will be the voltage drop across R subscript 2?

14.2 V
45.0 V
9.47 V
21.3 V

Answer 1

No idea how to approach this one

Answer 2

@Shadow

Answer 3

The question is asking u to find the votage across \(R_2\)

Step 1 : Find the total current for the whole circuit

Answer 4

As u can see,the resistors are arranged In series

Answer 5

equivalent resistance of resistors in series=\(R_1+R_2+R_3+...\)

Answer 6

use this formula
\(V=IR_{eff}\) to find the total current
where
\(V=total~voltage\)
\(I=total~current\)
\(R_{eff}=effective~resistance\)

Answer 7

\[I_{total} = \frac{ V_{total} }{ R_{total} }\]
\[R_{total} = 20 + 30 + 45 = 95 \Omega\]
\[I_{total} = \frac{ 45 }{ 95 } = 0.5 A\]
\[V = R I\]
\[V_{1} = (20)(0.5) = 10 V\]
\[V_{2} = (30)(0.5) = 15 V\]
\[V_{3} = (45)(0.5) = 22.5 V\]

45 not 12, *facepalm*

Answer 8

I rounded to 0.5 from 0.47, so if you do 30 times 0.47 you would get 14.2

Answer 9

Thank you! I think I got it :)

Sorry for vanishing, I had to deal with something!