Home
Class 12
PHYSICS
A boat which has a speed of 5km per hour...

A boat which has a speed of 5km per hour in still water crosses a river of width 1km along the shortest possible path in fifteen minutes. The velocity of the river water in km per hour is :-

A

1

B

3

C

4

D

`sqrt4 l`

Text Solution

Verified by Experts

The correct Answer is:
B
Promotional Banner

Topper's Solved these Questions

  • KINEMATICS-2D

    ALLEN |Exercise Exercise (O-2)|47 Videos

  • KINEMATICS-2D

    ALLEN |Exercise Exercise (S-2)|14 Videos

  • GRAVITATION

    ALLEN |Exercise EXERCISE 4|9 Videos

  • MOTION IN A PALNE

    ALLEN |Exercise SOLVED EXAMPLE|28 Videos

Similar Questions

Explore conceptually related problems

A boat which has a speed of 5 km per hour in still water crosses a river of width 1 km along the shortest possible path in fifteen minutes. The velocity of the river water in km per hour is :-

A boat man can row with a speed of 10 km/hr. in still water. The river flow steadily at 5 km/hr. and the width of the river is 2 km. if the boat man cross the river with reference to minimum distance of approach then time elapsed in rowing the boat will be:-

A motorboat whose speed is 18km/h in still water takes 1 hour more to go 24 km upstream than to return downstream to the same spot. Find the speed of the stream.

A man can swim with a speed of 4.0 km/h in still water . How long does he take to cross a river 1.0 km wide if the river flows steadily at 3.0 km/h and he makes his strokes normal to the river current ? How far down the river does he go when he reaches the other bank ?

A river is flowing with velocity 5km//hr as shown in the figure. A boat start from A and reaches the other bank by covering shortest possible distance. Velocity of boat in still water is 3km//hr . The distance boat covers is.

A river 2 km wide is flowing at the rate of 2km/hr. A boatman, can row the boat at a speed of 4 km/hr in still water, goes a distance of 2 km upstream and them comes back. The time taken by him to complete his journey is

A boat can be rowed at 5 m/s on still water. It is used to cross a 200m wide river from the south bank to the north bank. The river current has uniform velocity of 3 m/s due east. (a) In which direction must it be steered to cross the river perpendicular to current ? (b) How long will it take to cross the river in a direction perpendicular to the river flow ? (c) In which direction must the boat be steered to cross the river in minimum time ? How far will it drift ?

A man wishes to swim across a river 0.5km. wide if he can swim at the rate of 2 km/h. in still water and the river flows at the rate of 1km/h. The angle (w.r.t. the flow of the river) along which he should swin so as to reach a point exactly oppposite his starting point, should be:-

ALLEN -KINEMATICS-2D-Exercise (O-1)
  1. Three ships A, B and C are in motion. The motion of A as seen by B is ...

    Text Solution

    |

  2. Wind is blowing in the north direction at speed of 2 m/s which causes ...

    Text Solution

    |

  3. A boat which has a speed of 5km per hour in still water crosses a rive...

    Text Solution

    |

  4. A man is crossing a river flowing with velocity of 5m//s. He reaches a...

    Text Solution

    |

  5. A motor boat is to reach at a point 30^@ upstream on the outer side of...

    Text Solution

    |

  6. A ball is thrown from the top of 36m high tower with velocity 5m//ss a...

    Text Solution

    |

  7. A particle moves in the xy plane and at time t is at the point vec r= ...

    Text Solution

    |

  8. A particle moves in the xy plane with a constant acceleration 'g' in t...

    Text Solution

    |

  9. Two particle A and B projected along different directions from the sam...

    Text Solution

    |

  10. Positions of two vechicles A and B with reference to origin O and thei...

    Text Solution

    |

  11. Two projectiles are thrown simultaneously in the same plane from the s...

    Text Solution

    |

  12. Two projectiles are thrown simultaneously in the same plane from the s...

    Text Solution

    |

  13. Two projectiles are thrown simultaneously in the same plane from the s...

    Text Solution

    |

  14. A particle leaves the origin with initial velocity vec(v)(0)=11hat(i)+...

    Text Solution

    |

  15. A particle leaves the origin with initial velocity vec(v)(0)=11hat(i)+...

    Text Solution

    |

  16. A particle leaves the origin with initial velocity vec(v)(0)=11hat(i)+...

    Text Solution

    |

  17. By the term velocity of rain, we mean velocity with which raindrops fa...

    Text Solution

    |

  18. By the term velocity of rain, we mean velocity with which raindrops fa...

    Text Solution

    |

  19. If 2×10^(6) electrons/s are flowing through an area of cross section o...

    Text Solution

    |

  20. The distance travelled by a particle starting from rest and moving wit...

    Text Solution

    |