When a man is stationary, rain appears at 30° from the vertical toward the east. When he runs east at 10 m/s, rain appears vertically downward. The magnitude of the vertical component of rain velocity is:
Options

Question

When a man is stationary, rain appears at 30° from the vertical toward the east. When he runs east at 10 m/s, rain appears vertically downward. The magnitude of the vertical component of rain velocity is:

Options

G1 Physics · Accepted Answer

The second observation implies that the actual horizontal rain component is 10 m/s east. Initially tan30° = (horizontal component)/(vertical component) = 10/ v y . v_y. v y ​ . Since tan30° = 1/√3, v y v_y v y ​ = 10√3 m/s. Hence option C is correct.