to a man walking due east at the rate of 2km/h ,rain drops to fall vertically and when he increase his speed to 4km/h ,it appears to meet him at 25degree find real direction and speed of rain?
Let Vm is the speed of man. Let V is the speed and Vhor is the horizontal component of the speed of rain drops, A as the angle between rain's direction and the normal. Vhor = V * sinA. Vhor = Vm1 V * sin25 = Vm2 V = Vm2 / sin25 = 4 / sin25 = 9.4648 km/h V * sinA = Vm1 A = asin(Vm1 / V) = asin(0.2113) = 12.1991 degrees.