When you travel 40 km towards east and then 10 km towards west, your net displacement is.
A car travels from A to B at a speed of 20 km/hr and returns at a speed of 30 km/hr. The average speed of the car for the whole journey is
A bike moves with a speed of 50 km/h for 30 minutes and then with a speed of 60 km/h for the next 30 minutes. The total distance covered by the bike is