Home
Class 12
PHYSICS
A force 2hati+3hatj+4hatk N acts on a bo...

A force `2hati+3hatj+4hatk` N acts on a body for 4 sec, produces a displacement of `(3hati+4hatj+5hatk)`m. the power used is

A

9.5 W

B

7.5W

C

6.5W

D

4.5W

Text Solution

Verified by Experts

The correct Answer is:
A
`W=vecF.vecS=(2hati+3hatj+4hatk).(3hati+4hatj+5hatk)`
`=2xx3+3xx4+4xx5=38J`
`P=(W)/(t)=(38)/(4)=9.5W`.
Promotional Banner

Topper's Solved these Questions

  • CONCEPT BUILDER

    DISHA PUBLICATION|Exercise Exercise-1 Concept Builder (topic 4:Collisions)|1 Videos

  • CONCEPT BUILDER

    DISHA PUBLICATION|Exercise Exercise-2 Concept Applicator|27 Videos

  • CONCEPT BUILDER

    DISHA PUBLICATION|Exercise Exercise-1 Concept Builder (Topic 2:Energy)|15 Videos

  • COMMUNICATION SYSTEM

    DISHA PUBLICATION|Exercise EXERCISE-2 : Concept Applicator|30 Videos

  • CURRENT ELECTRICITY

    DISHA PUBLICATION|Exercise EXERCISE-2 Concept Applicator|23 Videos

Similar Questions

Explore conceptually related problems

A force of 2 hati + 3 hatj + 4 hatk N acts on a body for 4 second and producesa displacement of (3 hati + 4 hatj + 5 hatk)m . The power used is

A force of 2i+3j+2k N acts on a body for 4 and produces a displacement of 3hati+4hatj+5hatk m calculate the power?

When a force vector vecF=(hati+2hatj+hatk) N acts on a body and produces a displacement of vecS=(4hati+hatj+7hatk) m, then the work done is

A force vecF = (5 hati + 4 hatj)N acts on a body and produces a displacement vecs = (6 hati - 5 hatj + 3 hatk)m . The work done will be

What is the work done when a force vec F =2hati +3hatj-5hatk units acts on a body, producing a displacement vec S =2hati+4hatj+3hatk units ?

A force vecF=5hati+6hatj+4hatk acting on a body, produces a displacement vecS=6hati-5hatk . Work done by the force is

A force vecF=(5hati+4hatj)N acts on a body and produces a displacement vecS=(6hati-5hatj+3hatk) m. The work done will be

DISHA PUBLICATION-CONCEPT BUILDER-Exercise-1 Concept Builder (topic 3:Power)
  1. A car of mass m starta from rest and accelerates so that the instyanta...

    Text Solution

    |

  2. The power of a motor pump is 2kW. How much water per minute the pump c...

    Text Solution

    |

  3. A body of mass m accelerates uniformly from rest to v1 in time v2. As ...

    Text Solution

    |

  4. Johnny and his sister Jane race up a hill.Johnny weights twice as much...

    Text Solution

    |

  5. if a particle F is applied on a body and it moves with a velocity v ,...

    Text Solution

    |

  6. An electric motor exerts a force of 40 N on a cable and pulls it by a ...

    Text Solution

    |

  7. An engine pumps water continously through a hose. Water leave the hose...

    Text Solution

    |

  8. If two person A and B take 2 s and 4 s, respectively to lift an object...

    Text Solution

    |

  9. A body of mass 10 kg moves with a constant speed v of 2 ms^(-1) along ...

    Text Solution

    |

  10. An engineer claims to have made an engine delivering 10 kW power with ...

    Text Solution

    |

  11. A force applied by an engine of a train of mass 2.05xx10^6kg changes i...

    Text Solution

    |

  12. A 10 m long iron chain of linear mass density 0.8 kg m^(-1) is hanging...

    Text Solution

    |

  13. A force 2hati+3hatj+4hatk N acts on a body for 4 sec, produces a displ...

    Text Solution

    |

  14. An elevator can carry a maximum load of 1800 kg (elevator + passengers...

    Text Solution

    |

  15. A car of mass m is driven with acceleration a along a straight level r...

    Text Solution

    |

  16. An engine is hauling a train of mass m on a level track at a constant ...

    Text Solution

    |

  17. An automobile moves under the action of a constant power supplied by i...

    Text Solution

    |

  18. Water falls from a height of 60 m at the rate 15 kg//s to operate a tu...

    Text Solution

    |

  19. Ten litre of water per second is lifted from well through 20m and deli...

    Text Solution

    |

  20. An automobile of mass m accelerates, starting from rest, while the eng...

    Text Solution

    |