Calculating Distance on a Rollercoaster Using Impulse Method

[Frank_Horrigan]

I am doing a project and one of the questions is to find the average force lost to friction. We measured a ball going down a "roller coaster" (it had 2 humps on it). WE have all the speeds and distances and accelerations, Now i calculated the energy lost to friction by taking the initial gravitational energy and subtracting the gravitational energy and kintetic energy after the first drop. So now I have the W in W=F x d but I can't figure out how to get the distance. Is there a way to calculate it or do I have to go measure it? It doesn't have a constant acceleration so I can't think of how I could calculate it.

 

[whozum]

You can't really find the "force" lost to friction, since the force isn't conserved or anything nice like that. The energy lost to friction is a much nicer answer.

 

[NateTG]

The friction also is very unlikely to be constant. If you want to figure out average friction, you might want to try using time. Getting the distance will involve measuring the track.

 

[Frank_Horrigan]

Nate that is what I am supposed to find, the Average force of friction. But I don't know what to do because don't i need a distance to use the equation W=F x d to solve for F?

I do have the times but i can not figure out how to encorporate them to find the average force of friction.

 

[NateTG]

Well, if it's a physical experiment you should probably pull out the measuring tape.

 

[Chris Danger]

What about using impulse, if you have the time and initial and final velocities? Then F(ave)*t = m*(Vf-Vi).