Question 682: Current Electricity

Question

If power dissipated in the 9 $$\Omega $$ resistor in the circuit shown is 36 watt, the potential difference across the 2 $$\Omega $$ resistor is

Accepted Answer

We have,
$$P = {{{V^2}} \over R}$$
$$ \Rightarrow 36 = {{{V^2}} \over 9}$$
$$ \Rightarrow V = 18$$
Current passing through the 9$$\Omega $$ resistor is
$${i_1} = {V \over R} = {{18} \over 9} = 2A$$
The 9$$\Omega $$ and 6$$\Omega $$ resistors are in parallel, therefore
$${i_1} = {6 \over {9 + 6}} 	imes i$$
where i is the current delivered by the battery.
$$ 	herefore i = {{2 	imes 15} \over 6} = 5A$$
Thus, potential difference across 2$$\Omega $$ resistor is
V = iR  = 5 ÃÂ 2   = 10V

Answer

4 volt

Answer

8 volt

Answer

10 volt

Answer

2 volt

Current Electricity

If power dissipated in the 9 $\Omega resistor in the circuit shown is 36 watt, the potential difference across the 2 \Omega $ resistor is

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