estian 4 of 22 Sapling Learning Map While hauling a log in the back of a flatbed
ID: 1872937 • Letter: E
Question
estian 4 of 22 Sapling Learning Map While hauling a log in the back of a flatbed truck are pulled over by the state police. Although the can't roll sid could have slid out the back of the truck when accelerating from rest. You daim that the truck couldn't possibly accelerate at the level needed to achieve such an effect. Regardiess, the police write a ticket anyway and now your day in court is eways, the police claim that the log The log has a mass of m 974 kg, the truck has a mass of M- 9250 kg. According to the truck manufacturer, the truck can accelerate from 0 to 55 mph in 22.0 seconds, but this does not account for the additional mass of the log Calculate the minimum coefficient of static friction needed to keep the log in the back of the truck. Number to the scientific literature, the coefficient of static friction between the log and the trailer bed should 0.840. Given this fact, answer the following be O o There s litle chance the log could have slid out the back O real danger O The police officer is correct. The log posed a The results are not conclusive OPrevcus @cnve Up &View; Souton Check Answer ONed Eri a owsExplanation / Answer
55 mph 24.6 m/s
The acceleration of the empty truck is a = v/t = 24.6m/s / 22s = 1.12 m/s²
which tells us that a force F = ma = 9250kg * 1.12 m/s = 10360 N can be generated.
With the log on it, then, the truck can only accelerate at
a = F / m = 10360 N / (9250+974)kg = 1.01 m/s²
Then the log will stay on the truck only if it accelerates at this rate, meaning
friction force = 1.01 m/s² * 974 kg = 986.96 N = 987 N
So Ff = 987 N = µmg = µ * 974kg * 9.8m/s²
µ = 0.103 minimum static friction coefficient
There is little chance the log could have slid out the back
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.