# Torque and Equilibrium Lab Physics

Topics: Mass, Force, Kilogram Pages: 2 (251 words) Published: February 29, 2012
Torque and Equilibrium
Purpose: Apply principle of static equilibrium to determine a coefficient of friction. Research Question: What is the coefficient of friction between a meter stick and wall? Hypothesis: Tying a piece of string on to the end of a meter stick, put the other end of the meter stick against the wall so that the meter stick is horizontal and does not slide down the wall. Hang a weight on the meter stick sliding it to a point where the meter stick is about to come off from the wall.

Data:
Θ = 43
Center of mass of meter stick: 0.5 m
Length of meter stick: 1 m
Mass of meter stick: 0.0842 kg
Location of weight: 0.83 m
Mass of weight: 0.5 kg

Evaluation of Data:
∑Τ =0 = mgr0 + wr1 – T*r2sin Θ
= .0842*9.8*.50 + 0.5*0.83*9.8 – T *1 sin 43
= 6.57 N = T

∑Fx = 0 = FN – T sin Θ
= FN – 6.57* cos 43
= 4.804 = FN

∑Fy =0= Ff + T sin Θ – mg-W
= Ff + 6.57 sin 43 – 0.0842*9.8 – 0.5*9.8
=1.24 N = Ff

µ = Ff/FN = 1.24/4.804 = 0.26

Percent Error: Error could have resulted from the holes in the wall since they were made from brick. The string that was attached to one end of the meter stick as well as the wall tended to move because the tape did not hold well.