Question

A body moves due East with velocity 20 km/hour and then due North with velocity 15 km/hour. The resultant velocity

• A. 5 km/hour
• B. 15 km/hour
• C. 20 km/hour
• D. 25 km/hour

Answer 1

Answer: (D)

25 km/hour

Answer 2

Resultant velocity $\ = \ \sqrt{\text{2}\text{0}^{2} + 15^{2}}$

= $\sqrt{400 + 225} = \sqrt{625} = 25\mspace{6mu} km ⥂ / ⥂ hr$