Question

Man running on a horizontal road at 8km/hr finds the rain falling vertically.he increases his speed to 12km/hr and finds that the drop makes angle 30 degree with the vertical.find the speed and direction of the rain with respect to the road.

Answer 1

Since when the person runs at 8 km/h the rain seems to be coming verticaly down thus the horizontal component of rain, Vx is 8 km/hWhen he incrreases his relative speed by 4 km/h with the horizontal component of rain, it seems to fall at an angle of 30 degrees with the vertical.It means the vertical component, Vy is: 4/Vy = tan 30i.e.Vy = 6.93 km/hV = 10.58 km/hand angle of falling is: tan-1(8/6.93)