Question

Two motorcycles M₁ and M₂ are heading towards each other with a speed of 30 kmh^-1 each. A bird flies off M at 60 kmh^-1 when distance between the motorcycles is 60km. It heads towards M, and then back to M₁ and so on. The total distance the bird moves till the motorcycles meet is

• A. 60 km
• B. 40 km
• C. 50 km
• D. 30 km

Answer 1

Answer: (A)

60 km

Answer 2

v_ert = 30 + 30 = 60 kmh^-1

Time in which motorcycles will meet

= $\frac{x}{v_{ret}} = \frac{60km}{60kmh^{- 1}}$ = 1

distance moved by bird in 1 hr = 60 × 1 = 60 km