Experiment 3: Vector Addition Part 2

Figure 3.1: Force Table

EQUIPMENT

Force Table(4) Pulleys(4) Mass HangersMassesLevel (TA’s Table)

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Experiment 3: Vector Addition Part 1 23

PROCEDURE

Part 1: Adding 2 Vectors

1. Your TA will provide you with 2 forces, ~A and ~B.Record them in the table. Use component additionto find the resultant vector ~R=~A+~B. Show yourwork in the space below.

Vector Magnitude (N) Direction, θ

~A

~B

Resultant

Part 2: Adding 3 Vectors Graphically

2. Your TA will provide you with a third force ~C.Record the vectors in the table. Use componentaddition to find the resultant vector ~R=~A+~B+~C

. Show your work in the space below.

Vector Magnitude (N) Direction, θ

~A

~B

~C

Resultant

Part 3: Verify Result from Part 2

3. Use the level to make sure the surface of the forcetable is horizontal.

4. Use the force table and the same procedure that youdesigned last week to test whether the resultant ~R isequivalent to ~A+~B+~C. (Hint: use the equilibrantvector). Take whatever measurements you need forthe procedure you designed and record them in thedata table below. Label all rows and columns. Xout any rows or columns you don’t need.

5. Compare your computation of the resultant vector(Part 2) with the force table measurement of theresultant vector (Part 3). Show your calculationsfor percent error in the space below.

QUESTIONS

1. Was your percent error larger or smaller than thepercent difference in last week’s lab? Why do youthink that is?

2. What sources of error could be contributing to:

a) Head-to-tail method of vector addition

b) Component method of vector addition

c) Experimental, force-table method of vector addi-tion

3. Four vectors are all in the same quadrant (ex: quad-rant 1). Can the sum of these vectors equal zero.Explain why or why not using components.

4. Four vectors are all in the same two adjacent quad-rants (ex: quadrants 1 and 2). Can the sum of thesevectors equal zero? Explain why or why not usingcomponents.

5. Describe what properties of the four vectors wouldbe required for the sum of the four vectors to equalzero

6. Design an experiment on the force table that wouldshow that breaking vectors into their x- and y-components is valid. (Hint: Adapt Procedure 1 bymaking a convenient choice for vectors A and B)