In the circuit diagram shown in the figure, the potential difference E is 20 V. (A) The potential difference across points C and D is $V_{CD}$ If the potentials $V_{AB}, V_{BC}, V_{CD}, V_{DE}$ are arranged in increasing order, then Choose the correct answer from the options given below: |
(C), (A), (B), (D) (A), (B), (D), (C) (B), (A), (D), (C) (D), (C), (B). (A) |
(C), (A), (B), (D) |
The correct answer is Option (1) → (C), (A), (B), (D) Given: $E = 20\,\text{V}$ Resistances: $R_{AB}=4\,\Omega,\; R_{\text{top (B–C)}}=12\,\Omega,\; R_{\text{bot (B–C)}}=4\,\Omega,\; R_{\text{top (C–D)}}=3\,\Omega,\; R_{\text{bot (C–D)}}=6\,\Omega,\; R_{DE}=1\,\Omega$ Equivalent resistance between B and C: $R_{BC}=\frac{12\times4}{12+4}=\frac{48}{16}=3\,\Omega$ Equivalent resistance between C and D: $R_{CD}=\frac{3\times6}{3+6}=\frac{18}{9}=2\,\Omega$ Total series resistance: $R_{\text{tot}}=R_{AB}+R_{BC}+R_{CD}+R_{DE}=4+3+2+1=10\,\Omega$ Current through the circuit: $I=\frac{E}{R_{\text{tot}}}=\frac{20}{10}=2\,\text{A}$ Potential differences: $V_{AB}=I\,R_{AB}=2\times4=8\,\text{V}$ $V_{BC}=I\,R_{BC}=2\times3=6\,\text{V}$ $V_{CD}=I\,R_{CD}=2\times2=4\,\text{V}$ $V_{DE}=I\,R_{DE}=2\times1=2\,\text{V}$ Increasing order: $V_{DE} , V_{CD} , V_{BC} , V_{AB}$ |