Question

Example

Rain appears to fall vertically to a man walking at a rate of 3km/h. At
a speed of 6 km/h, it appears to meet him at an angle of 45° of vertical.
Find out the speed of rain.​

Answer 1

4.24 km/h

Step-by-step explanation:

When the man walks at a rate of 3 km/h, the rain appears to fall vertically, which means it has the same horizontal rate, 3 km/h.

When the man walks at a rate of 6 km/h, the rain's horizontal velocity relative to the man is now 6 km/h − 3 km/h = 3 km/h. The rain meets the man at a 45 degree angle, so the vertical velocity is also 3 km/h.

Therefore, the total speed is:

v = √((3 km/h)² + (3 km/h)²)

v = 4.24 km/h