Question

Question #1bec2

Answer 1

If the bird was flying along OB @ 100km/hr making an angle `theta` with the North-South direction and wind was blowing in East direction @ 30km/hr, then the resultant velocity of bird along south direction became `v_r`

So `v_r=sqrt(100^2-30^2)=10sqrt91"km/hr"`

So time required to travel 450km will be `t=450/(10sqrt91)hr~~4.72hr`

And the angle `theta=sin^-1(30/100)~~17.5^@`