70 meters per second is equal to 252,000 meters per hour, that is, 252 meters per hour, which is exactly the speed of the bullet train.
Because the meaning of second speed is the distance passed in 1 second, and the meaning of speed is the distance passed in 1 hour, and 1 hour has 3600 seconds, so the method of conversion is to multiply the data of second speed by 3600.
70 times 3600 is equal to 252,000, in meters per hour. If you divide that by 1,000, you get 252 kilometers per hour.
70 meters per second is 252 kilometers per hour
70 m\/s = (70÷1000) km\/(1÷3600) hours = 252 km\/h
The unit conversion of this type of problem, first the meter on the numerator divided by 1000 into kilometers, while the denominator of 1 second divided by 3600, into hours, unit conversion is completed.
When you convert kilometers per hour to meters per second, you can do it the other way around.