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Question
Study the diagram:
- Calculate the total resistance of the circuit.
- Calculate the current drawn from the cell.
- State whether the current through 10 Ω resistor is greater than, less than or equal to the current through the 12 Ω resistor.
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Solution
a. R1 = 10 + 6 = 16 Ω (in series)
R2 = 12 + 4 = 16 Ω (in series)
Req = `(R_1 xx R_2)/(R_1 + R_2)` (in parallel)
= `(16 xx 16)/(16 + 16)`
= `(16 xx 16)/32`
= 8 Ω
b. Current drawn `I = V/R`
= `4/8`
= `1/2`
= 0.5 A
c. Because the equivalent resistance in both arms is 16 Ω, the current in the 10 Ω resistor will be equal to the current in the 12 Ω resistor. Thus, equal current will flow through the 10 Ω and 12 Ω resistors as well as in both arms.
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