Question

Two electric bulbs have resistances in the ratio 1 : 2. If they are joined in series, theenergy consumed in these are in the ratio _________.
i) 1 : 2
ii) 2 : 1
iii) 4 : 1
iv) 1 : 1

Answer 1

Answer:

it remain the same .1:2

Answer 2

Answer:

Ratio of energy is=1:2.

Explanation:

Since electrical energy is defined as=$I^{2} Rt$......................(1)

here I=electrical current, R=resistance,t=time

Since bulbs are joined in the series so electrical current is same.

for a same amount of time i.e. time=constant

$\frac{E.E_{1} }{E.E_{2} }=\frac{I^{2}Rt }{I^{2}Rt }$..................(2)

Given $\frac{R_{1} }{R_{2} } =\frac{1}{2}$

$\frac{E.E_{1} }{E.E_{2} }=\frac{R_{1}  }{R_{2}  }$

So,

$\frac{E.E_{1} }{E.E_{2} }=\frac{1 }{2 }$.

So ratio of energy is=1:2.