A person is strolling along a moving walkway at a constant velocity of + 1.00 m/s with respect tot he walkway, which moves at a constant velocity of + 0.50 m/s with respect to the ground. An observer on the ground is walking at a constant velocity of - 0.2 m/s. what is the velocity of the person on the walk way with respect to the observers on the ground?

A - 0.7 m/s

B + 1.3 m/s

C - 0.3 m/s

D + 1.7 ms

Answer: D 1.7 m/s

In order to find the velocity of the person on the walk way with respect to the person on the ground we have to apply relative velocity concept.

Consider the observer on the ground as B and the person walking on the pathway as A. The relative velocity is the velocity that the body A would appear to an observer on the body B and vice versa.

Mathematically speaking the relative velocity is the vector difference between the velocities of two bodies.

Relative velocity = Velocity of Body A - Velocity of Body B.

Velocity of the person walking on the walkway (A) = 1.5 m/s. (given)

Velocity of the observer on the ground (B) = - 0.2 m/s (given).

Relative velocity of object A with respect to B = 1.5 - (-0.2) = 1.7 m/s.

Thus the velocity of the person on the walk way with respect to the observers on the ground is 1.7 m/s.