Question

A 2m wide truck is moving with a uniform speed v₀ = 8m/s along a straight horizontal road. A pedestrian starts to cross the road with a uniform speed v when the truck is 4 m away from him. The minimum value of v so that he can cross the road safely is

(a) 2.62m/s 

(b) 4.6m/s 

(c) 3.57m/s 

(d) 1.414m/s

Answer 1

Correct option (c)

Explanation:

For safe crossing, the condition is that the man must cross the road by the time the truck covers the distance 4 + AC or 4 + 2cotθ