Home
Class 12
PHYSICS
A river 2 km wide is flowing at the rate...

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

Text Solution

Verified by Experts

The correct Answer is:
D
If displacement is zero in given time interval then its average velocity also will be zero. E.g. particle projects vertically upwards.
Promotional Banner

Topper's Solved these Questions

  • MOTION IN A PALNE

    ALLEN |Exercise Comprehension#1|3 Videos

  • MOTION IN A PALNE

    ALLEN |Exercise Comprehension#2|5 Videos

  • MOTION IN A PALNE

    ALLEN |Exercise EXERCISE-03|6 Videos

  • KINEMATICS-2D

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

  • NEWTON'S LAWS OF MOTION & FRICTION

    ALLEN |Exercise EXERCISE (JA)|4 Videos

Similar Questions

Explore conceptually related problems

A river 3m deep and 40m wide is flowing at the rate of 2 km/hr. How much water will fall into the sea in 2 minutes :-

A river 4.0 miles wide is following at the rate of 2 miles/hr. The minimum time taken by a boat to cross the river with a speed v=4 miles/hr (in still water) is approximately

A river 3 m deep and 40 m wide is flowing at the rate of 2 km per hour. How much water will fall into the sea in a minute?

A river is flowing at the rate of 6 km/hr. A swimmer swims across with a velocity of 9 km/hr w.r.t. water. The resultant velocity of the man will be in (km/hr):-

A river 400 m wide is flowing at a rate of 2.0 m//s. A boat is sailing at a velocity of 10.0 m//s with respect to the water In a direction perpendicular to the river. (a) Find the time taken by the boat to reach the opposite bank. (b) How far from the point directly opposite to the starting point does the boat reach the opposite bank?

Ramesh travells at the speed of 40km/hr. If he decreases his speed 4km each hour, then how much time he will taken to cover 216km?

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 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 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 -MOTION IN A PALNE-Assertion-Reason
  1. An iron ball and a wooden ball of the same radius are released from a ...

    Text Solution

    |

  2. A particle moves along a straight line OX. At a time t (in seconds) th...

    Text Solution

    |

  3. Two bodies A (of mass 1 kg) and B (of mass 3 kg) are dropped from heig...

    Text Solution

    |

  4. A river 2 km wide is flowing at the rate of 2km/hr. A boatman, can row...

    Text Solution

    |

  5. A particle moving along x-axis has acceleration f, at time t, given by...

    Text Solution

    |

  6. The position x of a particle with respect to time t along the x-axis i...

    Text Solution

    |

  7. Two cars A and B start moving from the same point with same velocity v...

    Text Solution

    |

  8. An object travels 2km at a speed of 20 m/s and another 5km at 30 m/s. ...

    Text Solution

    |

  9. Which of the following relations representing displacement x (t) of pa...

    Text Solution

    |

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

    Text Solution

    |

  11. A particle moves in a straight line with a constant acceleration. It c...

    Text Solution

    |

  12. A particle shows distance-time curve as given in this figure. The maxi...

    Text Solution

    |

  13. The velocity-time graph of an objects is as shown. The displacement du...

    Text Solution

    |

  14. A bus is moving with a speed of 10 ms^-1 on a straight road. A scooter...

    Text Solution

    |

  15. In 1.0 s, a particle goes from point A to point B , moving in a semici...

    Text Solution

    |

  16. A car acceleration form rest at a constant rate alpha for some time, a...

    Text Solution

    |

  17. A particle move a distance x in time t according to equation x = (t + ...

    Text Solution

    |

  18. A ball is droped from a high rise platform t = 0 starting from rest. A...

    Text Solution

    |

  19. A particle has an initial velocity (6hati+8hatj) ms^(-1) and an accele...

    Text Solution

    |

  20. A car acceleration from rest at a constant rate 2m//s^(2) for some tim...

    Text Solution

    |