A 5kg object slides 100m down a frictionless inclined plane dropping 45m. It then slides along a horrizontal surface with a coefficiet of kinetic friction of .75 intil it stops. How long does it take to stop after it leaves the inclined plane? I'm not sure how to get the time. Here's what I found: mgh=.5mv^2 10m/s/s*45m=.5 v^2 v=30 m/s So the object is going 30m/s when it hits the friction floor. I'm not sure what to do next.