Convert 50 kilometers to meters using the given conversions:
50 kilometers x 1000 meters/ km = 50,000 meters
The speed limit is 50,000 meters per hour.
1 hour = 3600 seconds.
Divide total meters per hour by 3600 seconds to get meters per second:
50,000 / 3600 = 13.89
The speed limit converts to 13.89 meters per second.
He is traveling 13.5 meters per second, which is less than 13.89 so he is traveling below the speed limit.