Solving Two-Car Accident with Friction: Step-by-Step Guide

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    Accident Friction
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Homework Help Overview

The discussion revolves around a physics problem involving a two-car accident at an intersection, where the cars collide and slide together due to friction. Participants are attempting to analyze the work done by friction and the implications of speed claims made by the drivers involved.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • The original poster attempts to derive an expression for the work done by friction, expressing it in terms of mass, gravitational acceleration, friction coefficient, and distance. Some participants question the correctness of the expression and suggest adding a negative sign to account for the work being negative.

Discussion Status

Participants are engaged in exploring the problem, with some providing guidance on the expression for work done by friction. There is an acknowledgment of confusion regarding the calculations, particularly concerning the speeds of the drivers and the resulting implications for the problem.

Contextual Notes

There are constraints regarding the accuracy of speed claims made by the drivers, and participants are navigating these claims to determine consistency with the given information. The problem context includes specific values for friction and skid distance, which are critical to the discussion.

la673
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please help if u can.
Consider the following two-car accident: Two cars of equal mass collide at an intersection. Driver E was traveling eastward, and driver N, northward. After the collision, the two cars remain joined together and slide, with locked wheels, before coming to rest. Police on the scene measure the length of the skid marks to be 9 meters. The coefficient of friction between the locked wheels and the road is equal to 0.9.

i kno this question has been posted in other forums, but I am tryin to work out the work doen by friction and keep gettin it wrong,
Write an expression for the work done on the cars by friction.
Express your answer symbolically in terms of the mass of a single car, the magnitude of the acceleration due to gravity , the coefficient of sliding friction , and the distance through which the two-car system slides before coming to rest.
i get 2*mu*m*g*d which it (the web program) tells me I am off by a multiplicative factor...


Each driver claims that his speed was less than 14 meters per second (50 mph). A third driver, who was traveling closely behind driver E prior to the collision, supports driver E's claim by asserting that driver E's speed could not have been greater than 12 meters per second. Take the following steps to decide whether driver N's statement is consistent with the third driver's contention.
 
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It's doing negative work on the car. Just add a negative sign in. BTW, do you go to sydney uni at all?
 
yup, so do u i take it? nd thanks for that it was driving me crazy... couldn't work out where i was wrong
 
No probs. The whole physics asignment is driving me crazy...
 
i kno wat u mean, now I am stuck on the next question... got 12.61 m/s which is wrong... then i used 13 (cause it says to nearest integer) nd its also wrong
 
Do you have msn? Maybe we can chat through there.
 

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