M-2  Equilibrium of Forces

  NOTE *.3in
This experiment is simple, short, and not worth a whole laboratory period for most students; however for those having difficulty with the concept of vector addition, it may be helpful to use it as Part I of the M3 experiment which follows. If M2 is assigned as a stand alone experiment, the instructor probably should somewhat expand and structure the measurements.

OBJECTIVE: To experimentally verify vector addition of forces.

APPARATUS:

*.3in

Circular horizontal force table with 360^o scale, pulleys, weight hangers, slotted masses, protractor, rulers.

 

Figure 1: The horizontal force table

SUGGESTIONS: *.3in

Choose two concurrent forces, each between 100 and 500 gram weight and not in the same direction. Add these two vectors to find the resultant force: use both a graphical construction and a numerical computation.

Check your result by setting up the two original forces on the force table, and find experimentally the single force which will hold them in equilibrium. Are the values found by the three methods consistent?

Repeat the experiment but use three different original forces.

QUESTION: If the weight hangers used all have identical masses, can their weight be neglected?