Home » Ask Physics » The question of minimum time and minimum distance in crossing a river.

Subscribe to Blog via Email

Enter your email address to subscribe to this blog and receive notifications of new posts by email.

Join 3,146 other subscribers

Archives

The question of minimum time and minimum distance in crossing a river.

Share with:



A man crosses a river in a boat if he crosses the river in minimum time he take 10min with a drift 120metre if he crosses the river taking shortest path he takes 12.5min find the width of the river


Comments

  1. ans is 200 m.
    as for shortest time the drift is
    x =V(w)*t………V(w) is the velocity of water
    120 m = V(w)*10 s
    V(w)=12 m/s

    also x=[ V(w)*d ]/V(m)…..V(m) is velocity of man.
    therefore by solving d=10V(m)

    now for shortest path
    d={V(m) – V(w)}^1/2 * T
    substuting the values we will get d=200m

Ask a Doubt

Post your Physics Doubts here

Name (required)

Email (required)

Subject

Message/Doubt/Question

Upload a file if required

askphysics@Twitter

  • Visualisation paradox of tension https://t.co/7z63FA5Zxk https://t.co/ftxQzoVMvP
    about 3 weeks ago

Half Yearly Exam Count Down

Half Yearly Exam Count Down KVS Ernakulam RegionOctober 17, 2017
The Half Yearly Examination for Kendriya Vidyalayas of Kerala starts from 17 October 2017
%d bloggers like this: