Question

Three resistors of \(6.0 \Omega, 2.0 \Omega\) and \(4.0 \Omega\) respectively are joined together as shown in figure. The resistors are connected to an ammeter and to a cell of e.m.f. 6.0 V. Calculate:

(a) the effective resistance of the circuit.

(b) the current drawn from the cell.

Answer 1

(a) Effective resistance: The \(4\ \Omega\) and \(2\ \Omega\) resistors are in series, giving \(6\ \Omega\). This branch is in parallel with the other \(6\ \Omega\) resistor:

\[R_{\mathrm{eq}}=\frac{6\times6}{6+6}\]

= 3 Ω

(The unit printed as W in the question is a typo; resistance is measured in ohms.)

(b) Current drawn:

\[I=\frac{V}{R}\]

\[=\frac{6}{3}\]

= 2 A