Question

Two resistances are connected in series as shown in the diagram.

(i) What is the current through the 5 ohm resistance?

(ii) What is the current through R?

(iii) What is the value of R?

(iv) What is the value of V? [5 MARKS]

Answer 1

Problem: 5 Marks

1. Given:
First resistance, $R_1=5\Omega$
Current through 5 ohm resistance, I = ?

2. From Ohm's law, $R=\frac{V}{I}$ We have, $I=\frac{V}{R}=\frac{V_1}{R_1}$

$I=\frac{10}{5}=2ampere$

Current through $5\Omega$ resistance = 2 ampere (2A)


Value of second resistance, R = ?
Potential difference applied by the battery, V = ?

3. Current through resistance R, I = ?
Since R is in series with $5\Omega$, same current will flow through it,
Current through resistance R = 2 A

4. From Ohm's law, $R=\frac{V}{I}$

$R_2=\frac{V_2}{I}$

$R_2=\frac{6}{2}=3ohms$

Resistance R has value = 3 ohms

5. From relation, $V=V_1+V_2$

$V=10+6=16volts$

$V=16volts$