# Temperature Friction in Thermophysics

Essay by jrodockCollege, Undergraduate July 2014

Effect of Temperature on Friction of A Surface

-How does changing the temperature of a surface affect it's coefficient of friction?

Research:

There are many known facts derived from the basic laws of friction and heat's effect on molecules that could possibly link temperature and friction. It is known that when heat is applied to molecules, they gain energy and thus move faster. Also, there have been multiple theories of the temperature of a frictional surface. One states that a hotter surface can smooth the tires of a car, which is an explanation as to why drag racers spin their wheels on the track before they start. Another is that because heat speeds up molecules, they tend to diffuse more, thus expanding and creating a more uneven surface as a whole. A study at Saint Louis University in St. Louis, Missouri was conducted to find a relationship between these two factors.

Experiments indicated primarily that an abrupt increase in temperature induces a steep decrease in velocity.(1)

Hypothesis: Due to the precedent lab in the research section, it is predicted that as the temperature of the pool increases, the velocity of the ball moving across it will decrease. This is applied to the theory that hotter molecules diffuse more to create more uneven surfaces. Also, it is predicted that because hotter molecules move faster, more will hit the ball as temperature increases, thus creating more opposite forces and more friction overall.

Dependent Variable: Velocity of the object on the surface. It will be calculated by using the equation distance over time. In other words, the respondent is the time it takes (ÃÂ±.005sec) for the object to travel a controlled distance (.465ÃÂ±.0005m).

Independent Variable: The temperature of the surface that the object is moving on (10.1, 20.5, ad 28.6ÃÂ±.005ÃÂC). The temperatures...