Home
Class 11
PHYSICS
An elevator that can carry a maximum loa...

An elevator that can carry a maximum load of 1500 kg (elvator+ passengers) is moving up with a constant speed of 2 `ms^(-1).` The frictional force opposing the motion is 3000 N. Find the minmum power delvered by the motor to the elevator in watts as well as in horse power `(g=10ms^(-2))`

A

`36.2 hp`

B

`26.1 hp`

C

`48.3 hp`

D

`12.3 hp`

Text Solution

Verified by Experts

The correct Answer is:
`(3)`

The downward force on the elevator os
`F = mg + f`
`F = 15000 + 3000 = 18000N` The motor must supply enough power to balance this force.
Hence, `P = FV = 18000 xx 2 = 36000`
`P = 36000/746 = 48.3 hp`
Promotional Banner

Topper's Solved these Questions

  • WORK , ENERGY & POWER

    NARAYNA|Exercise EXERCISE -III|54 Videos
  • WORK , ENERGY & POWER

    NARAYNA|Exercise EXERCISE IV|43 Videos
  • WORK , ENERGY & POWER

    NARAYNA|Exercise EXERCISE -II (C.W)|75 Videos
  • WAVES

    NARAYNA|Exercise Exercise-IV|56 Videos
  • WORK POWER AND ENERGY

    NARAYNA|Exercise Level-VI (Integer)|12 Videos

Similar Questions

Explore conceptually related problems

An elevator can carry a maximum load of 1800 kg (celevator + passengers) is moving up with a constant speed of 2 ms^(-1) . The friction force oppposite the motion is 4000 N .What is minimum power delivered by the motor to the elevator?

An elevator which can carry a maximum load of 1800kg is moving with a constant speed of 2ms^(-1) . The frictional force opposing the motino is 5000N . Calculate the minimum power delivered by the motor to the elevator in watt and hp ? Take g=10m//s^(2)

A lorry of mass 2000 kg is traveling up a hill of certain height at a constant speed of 10 m/s. The frictional resistance is 200 N, then the power expended by the coolie is : (g=10 m//s^(2))

A body of mass 10 kg moves with a constant speed v of 2 ms^(-1) along a circular path of radius 8 m. The power produced by the body will be

A train has a constant speed of 40 ms^(-1) on a level road against resistive force of magnitude 3xx10^(4) N . Find the power of the engine.

A 120 HP electric motor lifts an elevator having a maximum total load capacity of 3000 kg. If the frictional force on the elevator is 6000N, the speed of the elevator at full load is close to : (1 HP = 746 W, g = 10 ms^(-2) ).

A 60 HP electric motor lifts an elevator having a maximum total load capacity of 2000 kg. if the frictional force on the elevator is 4000 N, the speed of the elevator at full load is close to : ( 1 HP = 746 W, g = 10 ms ^( - 2 ) )

NARAYNA-WORK , ENERGY & POWER -EXERCISE -II (H.W)
  1. Two bodies of masses m(1) and m(2) (m(2) gt m(1)) are connected by a l...

    Text Solution

    |

  2. An engine pumps water through a hose pipe. Water passes through the pi...

    Text Solution

    |

  3. An elevator that can carry a maximum load of 1500 kg (elvator+ passeng...

    Text Solution

    |

  4. A particle is projected at t = 0 from a point on the ground with cert...

    Text Solution

    |

  5. The input power to an electric motor is 200 KW. Its efficiency is 80%....

    Text Solution

    |

  6. The human heart discharges 75 cm^(3) of blood per beat against an aver...

    Text Solution

    |

  7. A point size mass 100 gm is rotated in a vertical circle using a cord ...

    Text Solution

    |

  8. A vehicle is travelling along concave road then along convex road of s...

    Text Solution

    |

  9. The length of a simple pendulum is 1 m. The bob is given a velocity 7 ...

    Text Solution

    |

  10. Two balls marked 1 and 2 of the same mass m and a third ball marked 3 ...

    Text Solution

    |

  11. A particle of mass m moving eastward with a velocity V collides with a...

    Text Solution

    |

  12. A 10 gm bullet is fired from a rifle horizontally into a 5 kg block of...

    Text Solution

    |

  13. Three identical particles with velocities v0hati, -3v0hatj and 5v0hatk...

    Text Solution

    |

  14. From the top of a tower of height 100 m a 10 gm block is dropped freel...

    Text Solution

    |

  15. A steel ball of radius 2 cm is initially at rest. It is struck head on...

    Text Solution

    |

  16. A canon shell fired breaks into two equal parts at its highest point. ...

    Text Solution

    |

  17. A mass of 2.9 kg is suspended from a string of length 50 cm and is at ...

    Text Solution

    |

  18. In a smooth circular tube of radius R , a particle of mass m moving wi...

    Text Solution

    |

  19. A mass ‘m’ moves with a velocity ‘v’ and collides inelastically with a...

    Text Solution

    |

  20. In the figure, pendulum bob on left side is pulled a side to a height ...

    Text Solution

    |