Modeling Frictional Forces 9-21

Modeling Frictional Forces

Carlos H. Dhalia T. Ariel D

9-21-16

This lab was broken up into  4 parts . What this lab will cover is friction of static and kinetic. We will be doing different types of experiments to measure fricution

The stuff that will be used in this lab include, 4 blocks a flat surface , in this case we used a cut up door I believe it was, a pulley, weights , motion detector, and force sensor. 

Part 1 For the first part we attached a block to the string which went to a pulley and down to some mass. We found the breaking points of mass for 1 blockc, 2 blocks , 3 blocks and 4 blocks. (each block has different mass and the mass was appropriately added on). 

Trial 1 Mass 180g, mass on pulley 90g

Trial 2 Mass 320g, mass on pulley 180g

Trial 3 Mass 496g, mass on pulley 265g

Trial 4 Mass 629g, mass on pulley 330g 

After simple Calculation our static friction coefficient came out to .5

Part 2 of the lab was working with kinetic Friction. We again worked with the same blocks and found the coefficient of kinetic friction by pulling on the block with a force sensor at a constant acceleration.  (The force sensor was properly calibrated at 0 when at a horizontal position.) 

Masses on Trials are the same as part 1 of the lab

Trial 1-  .58 N 

Trial 2- .85N

Trial 3- 1.35N

Trial 4 -1.48N

The calculated kinetic friction was .2616

 Part 3 We found static friction from lifting the service until breaking point. we only did this with one mass which was of 180g. Although the mass doesnt matter because when we solved for the Static friction coefficient the mass cancels out along with gravity leaving a tan of our angle which we measured to be 21.8 degrees. The coefficient of static friction came out to be .4 a picture of our work will be below

Work part 2 and 3

Part 4 

For this part we will raise the surface a tad bit more to where the block slides down contently. We measured it to 25.5 degrees and the mass of the block was 180g we attached  a motion detector ad for it to acelerate at .939m/s down . After our calculation that will be posted below we fount the kinetic to be .37

Conclusion - This lab helped us learn and understand how to find the values for the coefficients of friction in different ways and using different tools. This also helped us understand how friction is linked with forces, angles , mass , tension etc. Cheers