Question 375: Current Electricity

Question

A wire when connected to $$220$$ $$V$$ mains supply has power dissipation $${P_1}.$$ Now the wire is cut into two equal pieces which are connected in parallel to the same supply. Power dissipation in this case is $${P_2}.$$ Then $${P_2}:{P_1}$$ is

Accepted Answer

Case 1 :
$${P_1} = {{{V^2}} \over R}$$
Case 2 :
The wire is cut into two equal pieces. Therefore the resistance of the individual wire is $${R \over 2}.$$ These are connected in parallel
$$	herefore$$ $${{\mathop{m R}
olimits} _{eq}} = {{R/2} \over 2} = {R \over 4}$$
$$	herefore$$ $${P_2} = {{{V^2}} \over {R/4}} = 4\left( {{{{V^2}} \over R}} ight) = 4{P_1}$$

Answer

$$1$$

Answer

$$4$$

Answer

$$2$$

Answer

$$3$$

Current Electricity

A wire when connected to $220 V mains supply has power dissipation {P_1}. Now the wire is cut into two equal pieces which are connected in parallel to the same supply. Power dissipation in this case is {P_2}. Then {P_2}:{P_1}$ is

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