Question

A motor boat is to reach to a point `30^(@)` upstream on other side of a river flowing with velocity `5 m//s`.Velocity of motor boat with respect to water is `5sqrt3m//sec`.The driver should steer the boat at an angle of
A. `30^(@)` up w.r.t. the line of destination from the starting point
B. `60^(@)` up w.r.t. normal to the bank
C. `120^(@)` w.r.t. stream direction
D. None of these

Answer 1

The velocity of motor boat is given as `vecV_(m)=vecV_(mw)+vecV_(w)`
`rArr (5)/(sintheta)=(5sqrt(3))/(sin120^(@))`
`rArr sin theta=1//2 rArr theta=30^(@)`