Two cars moving in the same direction have speeds of 100 kmh\(^{-1}\) and 130 kmh\(^{-1}\). What is the velocity of the faster car as measured by an observer in the slower car?
A
30 kmh-1
B
130 kmh-1
C
200 kmh
D
230 kmh-1
Verified Correct Answer: A.
Physical Principles & Numerical Solution
Since the cars are moving in the same direction, the velocity of a body A, Va,relative to another body B, Vb is given by V = Va - Vb
∴ the velocity of faster car is measured by the observer in the slower car is V = 130kmh-1 - 100 kmh-1 = 30 kmh-1
Source: WAEC / JAMB / NECO Classroom Archive (Record #14283)