Register to reply

Speed from a skidding stop

by umdece4
Tags: skidding, speed, stop
Share this thread:
umdece4
#1
Apr7-10, 07:08 PM
P: 4
1. The problem statement, all variables and given/known data

You are driving your car uphill along a straight road. Suddenly, you see a car run a red light and enter the intersection just ahead of you. You slam on your brakes and skid in a straight line to a stop, leaving skid marks 116 feet long. A policeman observes the whole incident and gives a ticket for exceeding the speed limit of 45 mph. When you get home, you read your physics text book and estimate that the coefficient of kinetic friction between your tires and the road is 0.5, and the coefficient of static friction is 0.80. You go back and measure the angle that the hill makes with the horizontal and find it to be 6 degrees. You look in your owners manual and find that the car weighs 1820 lbs. Find the speed (in MPH) at the instant that you slammed the brakes and determine for yourself if you should fight the traffic ticket in court.

2. Relevant equations



3. The attempt at a solution

I dont remember exactly what i did but i could not get the right answer. it ranged between 22.87 mph to 50.95 mph.
Phys.Org News Partner Science news on Phys.org
Bees able to spot which flowers offer best rewards before landing
Classic Lewis Carroll character inspires new ecological model
When cooperation counts: Researchers find sperm benefit from grouping together in mice

Register to reply

Related Discussions
Will time stop if we were able to go as fast as the speed of light? Special & General Relativity 13
Why stop at speed of light? General Physics 48
Velocity of a car skidding Introductory Physics Homework 7
Forces on a car skidding to a halt. Introductory Physics Homework 2
Skidding problem Introductory Physics Homework 4