Procedure

Each student will gather and analyze their own unique data. After one student has recorded their data, move the magnetic mounts to a new position for the second student's measurements.

For each measurement with the force scales, show a sketch in your notes of the partial force scale and indicate position on the scale read for the measurement. Use the scale labeled "N" (Newton). Of note, the force scale is a difficult scale to read because of the increments used

1. Prepare the setup as shown in the figure using three scales attached by strings to a common center. Avoid a symmetrical arrangement (prepare with clearly different angles between scales). A lamp shining down is used to help record the string locations from their shadows.

Three vectors are represented by the three strings pulling from a common center point. Vector direction given by the string direction from the center point. Vector magnitude is given by the spring scale reading in Newtons.

2. Accurately sketch on graph paper the location of the strings and record in your notebook a sketch of what each scale shows. The sketch will be used in the analysis to measure direction of the force vectors.

3.  Consider the accuracy of your measurements. Do this by clearly recording in your notes each aspect of an uncertainty and the amount you estimate for the uncertainty with any further notes related to this estimate.

• What would you estimate as an the uncertainty (quote as ± ) in reading the scale? How accurate do you estimate the scales to be?
• How accurate are your angular measurements? Consider the uncertainty in reading the protractor scale and and the accuracy of locating the strings.