A thief was noticed by a policeman from a distance of 80 metres. The speed of the thief is 21 km/h and the policeman is 20 km/h. What is the distance between them after 18 seconds?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 85 metres.
Relative speed = 21 - 20 = 1 km/h = 5/18 m/s
Distance covered = (5/18) × 18 = 5 m
The thief is moving away from the policeman.
Final distance between them = 80 + 5 = 85 m