Finding the coefficient of sliding friction (Lab 3)
The aim is to find the coefficient of sliding friction μ between a wooden block and a table surface. Pull the block slowly along the horizontal table with a dynamometer at constant velocity: in uniform motion the resultant is zero, so the dynamometer reading F equals the friction force. The block’s weight P = mg equals the normal force N on the table (N = P). Measure the weight of the block and loads with the dynamometer too. Then compute μ = F/N. Add a load on the block to change N and compare: μ should come out about the same. Repeat each pull 3 times and take the average. Work under the teacher’s supervision.
Table: № | N (N) | F (N) | μ = F/N. Pull the block 3 times (with at least 3 loads). Safety: keep the dynamometer and loads away from the table edge, pull slowly, and keep your fingers clear.