MyQuestionIcon

1

You visited us 1 times! Enjoying our articles? Unlock Full Access!

Average and Instaneous Power

If R1 and ...

Question

If $R_{1}$ and $R_{2}$ are filament resistances of a 200 W and a 100 W bulb respectively, designed to operate on the same voltage, then:

A

R_{1} = R_{2}

No worries! We‘ve got your back. Try BYJU‘S free classes today!

B

R_{2} = 2 R_{1}

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

C

R_{2} = 4 R_{1}

No worries! We‘ve got your back. Try BYJU‘S free classes today!

D

R_{1} = 4 R_{2}

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

The correct option is C $R_{2} = 2 R_{1}$
Power, $P = \frac{V^{2}}{R}$
For first bulb power, $P_{1} = \frac{V_{1}^{2}}{R_{1}}$
For second bulb power, $P_{2} = \frac{V_{2}^{2}}{R_{2}}$
Divide the above equations:
$\frac{P_{1}}{P_{2}} = \frac{V_{1}^{2} \times R_{2}}{V_{2}^{2} \times R_{1}}$
Substitute: $P_{1} = 200 W$ and $P_{2} = 100 W$ and $V_{1} = V_{2}$ (as bulbs operate at same voltage)

$\Rightarrow \frac{200}{100} = \frac{R_{2}}{R_{1}}$

$\Rightarrow R_{2} = 2 R_{1}$

Suggest Corrections

thumbs-up

0

Similar questions

R_{1}

R_{2}

are respectively the filament resistances of a

200 w a t t

100 w a t t

bulb designed to operate on the same voltage

R_{1}

R_{2}

are, respectively the filament resistance of a 200 watt bulb and a 100 watt bulb designed to operated on the same voltage.

R_{1}

R_{2}

are respectively the filament resistance of a

200 W

100 W

bulb designed to operate on the same voltage then

Q. Two electric bulbs, rated for the same voltage, have powers of 200 W and 100 W, respectively. If their resistances are

r_{1}

r_{2}

, respectively, then

R_{1}

R_{2}

be two relations defined on a non empty set A. Which of the following statements is false? Give reasons in support of your answer.
(a) If

R_{1}

R_{2}

are reflexive, then so is

R_{1} \cap R_{2}

R_{1}

R_{2}

are symmetric, then so is

R_{1} \cup R_{2}

R_{1}

R_{2}

are transitive, then so is

R_{1} \cup R_{2}

R_{1}

R_{2}

are transitive, then so is

R_{1} \cap R_{2}

R_{1}

R_{2}

are symmetric, then so is

R_{1} \cap R_{2}

View More

Join BYJU'S Learning Program

similar_icon

Related Videos

lock

Power

PHYSICS

Watch in App

explore_more_icon

Explore more

Average and Instaneous Power

Standard XII Physics

Join BYJU'S Learning Program

CrossIcon