posted by Dianne .
When I look into my beautiful 1981 Vanagon's rear view mirror, I see a semi-truck coming toward me way too fast. The truck has lost its brakes and is traveling at 140 km/hour down the steep mountain road we're on. At the last second, the truck exits onto an escape ramp that has a "gentle" uphill slope of 12 degrees. What is the minimum length of the ramp needed to make sure the truck will stop?