How do weight, surface area, and speed affect the force of friction?

[grade11]

Investigation: Factors Affecting Friction

Design and complete an investigation to determine how the following factors affect the force of friction:

-Wieght

- Surface Area

-Speed

You will need to measure the magnitude of the force of friction. Since the magnitude of the force that is provided by an elastic band is directly related to the distance the elastic band is stretched, it is apropriate to substitude the distance strecthed for the force. You will need objects with identical masses, whose surface area can be easily altered (such as a tissue box). Remember that regardless of what velocity you choose, you must try to keep it as constant as possible.



WAT! lol please explain to me what all this means and give me a detailed plan of what i need to do to accomplish this task THANKS

 

[Mindscrape]

I have no idea what it means, and that is why it is your job to tell us your initial thoughts on the problem. Nobody here is going to have a clue what the elastic band apparatus is supposed to be without you going into some detail about how it works, and how your experiment could work around it.

 

[andrevdh]

If you pull the object at a constant speed the force you are applying (a horizontal force should be applied on a level surface) will be equal to the frictional force. You can determine the magnitude of this force by using the extension of the elastic (which you should calibrate by hanging masses from it and measuring its extension).

 

[grade11]

oik ill see what i can do with that...so basically calibrate an elastic band pull objects with it the objects should differen in wieght and surface area and they should be pulled at different speeds as well how many objects should i use?

 

[andrevdh]

I should think that a minimum of four measurements for each investigation is needed, but your results (graph f on y and the independent variable [weight, size of surface area or speed] on the x) will dictate how many.

For each type of invstigation you need to keep the other two constant. That is if you decide to investigate the "friction force - weight" relation then you need to keep the surface area and speed the same for all the measurements while changing the weight for each measurement.

It goes without saying that since the coefficient changes when the two involved surfaces are changed you should do these investigations without changing the surfaces that rubs against each other.