Question

Rain is falling vertically a speed of $30m/s$. A woman rides a bicycle with a speed $10m/s$ in the north to south direction. What is the direction in which should hold her umbrella?

Answer 1

• Since she is moving from north to south direction rain will falls at same angle with vertical.
  
• Here, Rain will appear to fall by moving an angle ${\tan }^{-1}\left(\frac{1}{3}\right)$
  
• So lady should hold umbrella at an angle ${\tan }^{-1}\left(\frac{1}{3}\right)$ with vertical.