Question 104: Current Electricity

Question

Figure shows three resistor configurations R1, R2 and R3 connected to 3 V battery. If the power dissipated by the configuration R1, R2 and R3 is P1, P2 and P3, respectively, then

Accepted Answer

We know that $$P = {{{V^2}} \over R}$$
If potential is constant we have
$$P \propto {1 \over R}$$
Case I
Hence, this is a clear case of wheat stone bridge R$$_1$$ = 1 $$\Omega$$
Case II
Equivalent resistance (R$$_2$$)
$$	herefore$$ $${1 \over {{R_2}}} = {1 \over 2} + {1 \over 1} + {1 \over 2} = {{1 + 2 + 1} \over 2} = {4 \over 2} = 2\,\Omega $$
Hence, $${R_2} = {1 \over 2} = 0.5\,\Omega $$
It is clear that the equivalent resistance (R$$_2$$) will be less than 1 $$\Omega$$.
Case III
Hence, R$$_3$$ = 2 $$\Omega$$
Since, R$$_2$$  P$$_1$$ > P$$_3$$ ($$ \because $$ $$P \propto {1 \over R}$$)

Answer

P1 > P2 > P3

Answer

P1 > P3 > P2

Answer

P2 > P1 > P3

Answer

P3 > P2 > P1

Current Electricity

Figure shows three resistor configurations R1, R2 and R3 connected to 3 V battery. If the power dissipated by the configuration R1, R2 and R3 is P1, P2 and P3, respectively, then

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