Home
Class 12
PHYSICS
When two resistances R1 and R2 are conn...

When two resistances `R_1 and R_2` are connected in series , they consume 12 W powers . When they are connected in parallel , they consume 50 W powers . What is the ratio of the powers of `R_1 and R_2` ?

A

`1//4`

B

4

C

`3//2`

D

3

Text Solution

Verified by Experts

The correct Answer is:
C

`(P_(1)P_(2))/(P_(1)+P_(2)) = 12 rArr P_(1)P_(2) = 12 xx 50, therefore P_(1) + P_(2) = 50`
`rArr (P_(1)-P_(2))^(2) + 4P_(1)P_(2) = (P_(1) + P_(2))^(2)`
`P_(1) = 30W, P_(2) = 20 W`
`P_(1)/P_(2) = 30/20 = 3/2`
Promotional Banner

Topper's Solved these Questions

  • CURRENT ELECTRICITY

    ERRORLESS|Exercise PAST YEARS QUESTIONS |76 Videos
  • CURRENT ELECTRICITY

    ERRORLESS|Exercise ASSERTION AND REASON|26 Videos
  • CURRENT ELECTRICITY

    ERRORLESS|Exercise NCERT BASED QUESTIONS (DIFFERENT MEASURING INSTRUMENTS) |74 Videos
  • ATOMIC AND NUCLEAR PHYSICS

    ERRORLESS|Exercise Assertion and Reason|23 Videos
  • ELECTROMAGNETIC INDUCTION

    ERRORLESS|Exercise ASSERTION & REASON|20 Videos

Similar Questions

Explore conceptually related problems

When three identical bulbs are connected in series. The consumed power is 10W. If they are now connected in pa rallel then the consumed power will be:-

Two equal resistances are connected in seires across a battery and consume a power P If these are connected in parallel, then power consumed will be

Five equal risistors when connected in series dissipted 5 W power. If they are connected in parallel, the power dissipated will be

Five equal resistors when connected in series dissipated 5 W power. If they are connected in paralle, the power dissipated will be

When two resistors of resistances R_1 and R_2 are connected in parallel, the net resistance is 3 Omega . When connected in series, its value is 16 Omega . Calculate the values of R_1 and R_2 .

Two resistance R_(1) and R_(2) when connected in series and parallel with 120 V line, power consumed will be 25 W and 100 W respectively. . Then the ratio of power consumed by R_(1) to that consmed by R_(2) will be

Two equal resistances when connected in series to a battery ,consume electric power of 60 W .If these resitances are now connected in parealled combination to the same battery ,the electric power cansumed will be :

Two bulbs which consume powers P_(1) " and P_(2) are connected in series. The power consumed by the combination is

When two identical batteries of internal resistance 1Omega each are connected in series across a resistor R, the rate of heat produced in R is J_1 . When the same batteries are connected in parallel across R, the rate is J_2 = 2.25 J_2 then the value of R in Omega is

The Total resistance when connected in series in 9 Omega and when connected in parallel is 2 Omega The value of two resistance are

ERRORLESS-CURRENT ELECTRICITY-NCERT BASED QUESTIONS (HEATING EFFECT OF CURRENT)
  1. An electric motor operator on 15 V supply, draws a current of 5 A and ...

    Text Solution

    |

  2. A heater is designed to operate with a power of 1000W in a 100 V line....

    Text Solution

    |

  3. A resistor R(1) dissipates the power P when connected to a certain gen...

    Text Solution

    |

  4. Two identical heaters rated 220 V , 1000 W are paced in series with ea...

    Text Solution

    |

  5. Two bulbs of 100 W and 200 W working at 220 volt are joined in series ...

    Text Solution

    |

  6. Three electric bulbs of rating 60 W each are joined in series and then...

    Text Solution

    |

  7. Three electric bubls of 200W, 200 W and 400W are shown in figure. The ...

    Text Solution

    |

  8. When two resistances R1 and R2 are connected in series , they consume...

    Text Solution

    |

  9. Three equal resistor connected in series across a source of enf toget...

    Text Solution

    |

  10. Two electric bulbs marked 40W, 220V and 60W, 220V when connected in se...

    Text Solution

    |

  11. A 5^(@)C rise in the temperature is observed in a conductor by passing...

    Text Solution

    |

  12. A 12 V lead accumulator is being charged using 24 V supply with an ext...

    Text Solution

    |

  13. A coil takes 15 min to boil a certain amount of water, another coil ta...

    Text Solution

    |

  14. An electric kettle has two heating coils. When one coil is used, water...

    Text Solution

    |

  15. An immersion heater is rated 836 watt . It should heat 1 litre of wate...

    Text Solution

    |

  16. A wire of length L and 3 identical cells of negligible internal resist...

    Text Solution

    |

  17. A coil of wire of resistance 50 Omega is embedded in a block of ice. I...

    Text Solution

    |

  18. Flash light equipped with a new set of batteries, produces bright whit...

    Text Solution

    |

  19. The material of fuse wire should should have

    Text Solution

    |

  20. A fuse wire with radius 1 mm blows at 1.5 amp . The radius of the fuse...

    Text Solution

    |