PROBLEM 4 (15 marks)
Using the information in problem 3 and the static coefficient of friction of the road as 0.7, will the truck be in danger of rolling back down the slope? Use appropriate diagrams and include all your working to justify your answer.
PROBLEM 3 (15 marks)
Roads going down through mountains regions are often steep. As a precaution for heavy traffic areas, particularly for trucks, safety ramps are constructed in case vehicles’ brakes fail.
A truck’s brakes have failed while travelling down the Toowoomba Range. The truck gains velocity as it has travelled the range, before the driver finds the safety ramp. The truck’s velocity has increased to 100km/h by the time it has reached the start of the safety ramp, the ramp has a slope of 30° from the horizontal and the truck takes 10s to roll to a complete stop. For a minimum safe stopping distance, what will be the total horizontal distance of the escape ramp?
I've done question 3, I think it was fairly easy. The horizontal leg of the ramp is 120m, the incline leg is 139m. Rate of acceleration (deceleration) is -2.78m/s/s
question 4, I am completely stumped. I have drawn a free box diagram and indicated all of the relevant forces, but I have no idea how to calculate what's necessary to find a solution?
The Attempt at a Solution
Don't know where to start!