Question

A motorcycle travelling on the highway at a speed of $120km/h$ passes a car travelling at a speed of 90 km/h. From the point of view of a passenger on the car, what is the velocity of the motorcycle?

• A. $43km/h$
• B. $23km/h$
• C. $30km/h$
• D. $29km/h$

Answer 1

Answer: (C)

$30km/h$

Given that,

Speed of motorcycle $v_m=120km/h$

Speed of car $v_c=90km/h$

The relative velocity is defined as,

$v_{mc}=v_m-v_c$

Where, $v_c$ = speed of car

$v_m$ = speed of motorcycle

The velocity of the motorcycle is

$v_{mc}=120-90$

$v_{mc}=30km/h$

So, The velocity of motorcycle is 30 km/h.

Hence, C is correct.