A vehicle moves in a straight line with an acceleration of 6 km/h^2. By how much does the speed change each second? Answer in units of km/h.

1 Answer
Nov 19, 2017

See below.

Explanation:

This problem is essentially asking you to convert the given acceeration with units of #"km/h"^2# to a different unit.

Acceleration is the rate change of speed per unit of time. We want the speed to be in units of #"km/h"#, but since we want to see how much the speed changes each second, the final unit should have the unit #("km/h")/"s"#.

#"6 km"/cancel("h"^2)^color(blue)"h" * ("1" cancel"h")/"3600 s" = "1 km"/ ("600 h" * "s") = "1 km/h"/ ("600 s") ~~ "0.002 km/h"/"s"#

Thus, for each increase in one second, the speed increases by about #"0.002 km/h"#.