In this question two important things are already given . Let us first note them down first. Speed of the bus = 75.0 km/hr or 21/s Time before it finally stops = 21second. It is better to calculate in miles per second as the time given is in second. This will make the problem easier. We already know that Distance traveled = Speed * time = 21 * 21 meters = 441 meters So the bus will stop after traveling a distance of 441 meters. This distance can be converted to kilometer as well very easily now. 1000 meter = 1 km 441 meters = 441/1000 km = 0.441 km So the bus will stop after 441 meters or 0.441 kilometers.
A bus slows down uniformly from 75.0 km/h ( 21 m/s) to 0 km/h in 21 s. How far does it travel before stopping