Question

You are roller-skating at 3 m/s west, and your friend is roller-skating at 3 m/s east. What is your friend's velocity relative to you

Answer 1

If you use your ruler and clock to measure your friend's speed and direction WHILE you're skating along, you'll decide that your friend is skating away from you toward the East, at 6 m/s .

Answer 2

Answer:

9 m/s towards east

Explanation:

Consider east direction as positive and west direction as negative. A person is roller skating at 3 m/s west that is -3 m/s. His friend is moving at +3m/s

The relative velocity of object a with respect to be b can be calculated as follows:

$v_{ab} = v_b-v_a\\ v_r=(3 - (-3)) m/s = 9 m/s$ towards East.