Question

A car starts at P, and travels at a speed of 50 km h−1 for 6 hours. It comes to rest at Q. 2 hours after the first car starts, another car starts at P and moves towards Q.

In order to reach the point Q at the same time as the first car, with what speed must the second car travel?

Open in App

Solution

The correct option is **B** 75 km h−1

Given:

Speed of first car = 50 km h−1

Time travelled by the first car = 6 h.

∴ Distance between P and Q = 50×6=300 km

Now, the second car starts 2 hours after the first car.

To reach the point Q at the same time as the first car, the second car should cover the distance between P and Q in the remaining time.

Distance to be covered = 300 km

Remaining time = 6 - 2 = 4 h

Required speed = 3004 = 75 km h−1

Given:

Speed of first car = 50 km h−1

Time travelled by the first car = 6 h.

∴ Distance between P and Q = 50×6=300 km

Now, the second car starts 2 hours after the first car.

To reach the point Q at the same time as the first car, the second car should cover the distance between P and Q in the remaining time.

Distance to be covered = 300 km

Remaining time = 6 - 2 = 4 h

Required speed = 3004 = 75 km h−1

0