To calculate the time taken by a bus to cover a distance, you can use the formula:
Time = Distance / Speed
In this case, the distance is given as 50 km and the speed is given as 20 m/s. However, it's important to ensure that the units are consistent, so let's convert the distance to meters:
50 km = 50,000 meters
Now, we can plug the values into the formula:
Time = 50,000 meters / 20 m/s
Time = 2500 seconds
Therefore, the bus will take 2500 seconds to cover a distance of 50 km when moving at a speed of 20 m/s.