Answer:
Explanation:
Given
Velocity of helicopter relative to air 12.5 m/s to west
In vector form
[tex]V_{ha}=-12.5\hat{i}[/tex]
where [tex]V_h[/tex]= velocity of helicopter relative to ground
Also the velocity of air
[tex]V_a=4.55\hat{j}[/tex]
[tex]V_{ha}=V_h-V_a[/tex]
[tex]V_h=V_{ha}+V_a[/tex]
[tex]V_h=-12.5\hat{i}+4.55\hat{j}[/tex]
Speed relative to east[tex]=\sqrt{12.5^2+4.55^2}[/tex]
=13.302
For Direction
[tex]tan\theta =\frac{4.55}{-12.5}[/tex]
[tex]180-\theta =20[/tex]
[tex]\theta =160^{\circ}[/tex] relative to east
For 1 km travel it takes
[tex]t=\frac{1000}{13.302}=75.17 s[/tex]