Question

13 mark for review cars a and b are moving with the speeds relative to the ground indicated in the figure. the positive direction is to the right. what is the velocity of car b relative to car a? a -30 m/s b -20 m/s

Explanation:

Step1: Recall relative - velocity formula

The formula for relative velocity is $v_{BA}=v_B - v_A$, where $v_{BA}$ is the velocity of B relative to A, $v_B$ is the velocity of B with respect to the ground, and $v_A$ is the velocity of A with respect to the ground.

Step2: Identify given velocities

We are given that $v_A = 30\ m/s$ and $v_B=10\ m/s$.

Step3: Calculate relative velocity

Substitute the values into the formula: $v_{BA}=10 - 30=- 20\ m/s$.

Answer:

B. $-20\ m/s$