**·**2014-02-09 01:46:21

Let boats speed be V and stream speed be U and distance be S

For boat A total time takes is given by t1= S/(v+u) for donstream and t2 = S/v-u for upstream

T_{a}= t1 + t2 = 2SV/ v^{2} - u^{2}

For Boat B its quite complicated but still...

B has to Perpendicular so it has to make an angle x such that

Vsinx= U ....sinx= U/V

we did this one in river boat problem in cases where drift has to be minimum

now the cos component of V will help it moving forward.

Vcosx=√V^{2} - U^{2} (by trigo)

Now since in perpedicualr direction the speed remains const through out so

T_{b}= 2S/√V^{2} - U^{2}

T_{a}/T_{b}= V/√V^{2} - U^{2}

= 1.2/√1.2^{2} - 1

=1.8

- Himanshu Giria thanks...

·0·Reply·2014-02-09 03:07:21