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Question
With reference to the diagram shown below calculate:
(i) The equivalent resistance between P and Q.
(ii) The reading of ammeter.
(iii) The electrical power between P and Q.
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Solution
(i) `1/"R" = 1/4 + 1/6 = (3 + 2)/12 = 5/12`
So, equivalent resistances
`= 12/5 = 2.4 Omega`
(ii) Here, R = 2.4 Ω
E = 2 × 2 = 4 V
From E = IR
I = `"E"/"R"` or I = `4/2.4 = 1.66` A
(iii) Power between P and Q
= I2R
= (1.66)2 × (2.4) = 6.66 watts
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