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

In summary, two cars collided at an intersection with equal mass and remained joined together while sliding with locked wheels until coming to rest. The length of the skid marks measured by police was 9 meters and the coefficient of friction between the wheels and the road was 0.9. The work done on the cars by friction can be expressed as 2*μ*m*g*d, where μ is the coefficient of sliding friction, m is the mass of a single car, g is the magnitude of acceleration due to gravity, and d is the distance the two-car system slides before coming to rest. The third driver's statement that driver E's speed was not greater than 12 meters per second is consistent with driver N's claim that his speed
  • #1
la673
13
0
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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  • #2
It's doing negative work on the car. Just add a negative sign in. BTW, do you go to sydney uni at all?
 
  • #3
yup, so do u i take it? nd thanks for that it was driving me crazy... couldn't work out where i was wrong
 
  • #4
No probs. The whole physics asignment is driving me crazy...
 
  • #5
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
 
  • #6
Do you have msn? Maybe we can chat through there.
 
  • #7

1. What is friction and how does it affect a two-car accident?

Friction is a force that opposes the motion of two objects in contact with each other. In a two-car accident, friction plays a crucial role in determining the severity of the collision. The amount of friction between the two vehicles can affect the speed, direction, and damage caused by the impact.

2. How can I determine the coefficient of friction between two cars?

The coefficient of friction can be determined by conducting experiments with different surfaces and measuring the force required to move the cars at a constant speed. This value can also be found in tables or by using specialized instruments.

3. What factors can influence the coefficient of friction in a two-car accident?

The coefficient of friction can be affected by various factors such as the weight of the vehicles, the type of tires, the condition of the road surface, and the presence of any external substances like oil or water on the road. These factors can either increase or decrease the friction between the two cars.

4. How can I calculate the stopping distance of a car during a two-car accident?

To calculate the stopping distance, you need to know the initial speed of the cars, the coefficient of friction, and the deceleration rate. Using the equation d = (v^2) / 2u, where d is the stopping distance, v is the initial speed, and u is the coefficient of friction, you can determine the distance needed for the car to come to a complete stop.

5. Are there any safety precautions I should take when conducting experiments on two-car accidents with friction?

Yes, it is important to take proper safety precautions when conducting experiments on two-car accidents with friction. This includes wearing protective gear, choosing a safe and controlled environment, and following all safety protocols. It is also important to have an experienced researcher or instructor supervising the experiment.

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