Lab Friction Lab Friction

Buy here: http://homeworknumber.one/products.php?product=Lab- Friction Data Table 1.​ Flat Board. Data Table2.​ Flat Board-Block Sideways. How does the coefficient of static friction compare with the coefficient of kinetic friction for the same surfaces and areas? Why is it important to reduce friction during the operation of machinery? How does grease or oil affect the coefficient of friction?