Answer to Question #86232 in Mechanics | Relativity for Krishna

Question

Every 10 minutes one motor car starts from A towards B. The distance between A and B is 60 km. The speed of the motor car is 60 km/hr. The number of cars met by a passenger riding in a car which starts from B to A simultaneously with one of the motor cars from A will be ______. (The car in which the passenger is also travels at 60 km/hr)

Answer 1

The passenger will overcome the distance between A and B in one hour.

The distance between each motor car is 10 km, because their speed is 60 km/h and they start to go every 10 minutes.

As 60 km/h = 1 km/min, then the approach speed of the passenger and the motor car is 2 km/min. So passenger will meet a motor car each 5 minutes (10 km / 2km/min).

On 60 km distance starting from the 0 minute passenger will meet 13 motor cars meeting them each 5 minutes.

Answer

A passenger will meet 13 motor cars.