Acar is traveling at 20meters/seconds and is brought to rest by applying brakes over a period of 4 seconds what is it's average acceleration over this time interval?

v=vo-at<=>0=20-4a<=>4a=20=>a=5 m/s^2

some think that theories become laws, but theories and laws have separate and distinct roles in the scientific method. a law is a description of an observed phenomenon in the natural world that hold true every time it is tested. it doesn't explain why something is true; it just states that it is true.