Revised Instructions for Windows Version of SHM program

Revised Instructions for Windows Version of SHM program

This simulation works much like the DOS simulation except that you control it with mouse clicks and/or entered numerical values.

Run the simulation in the usual manner from the Web or, to use the downloaded program, RUN menu or from Windows Explorer. The program is entitled SHM_Simulation and is posted under the Supervised Study Current Semester pages, Course Documents, Downloads, Physics I.

The following exercise is recommended:

Click on the Run Simulation button. You will see a point begin moving around the circle, accompanied by vertical and horizontal projection lines.

Note that the angular frequency, radius and other bits of information are displayed in boxes to the right of the simulation.

Note particularly how the clock time t is displayed in the box labeled t (sec), giving the time since the start of the simulation.

The angle theta is displayed in two text boxes, both labeled theta with the first showing the angle in decimal form, the second showing the angle as a multiply of pi.

The x and y coordinates of the projection lines are also displayed, in boxes labeled x and y.

Click on the Pause Simulation button and note the time t and angle theta. Click on the Restart button and you will see that the simulation starts from the point and clock time at which it was paused.
Click on the Run Simulation button and you will see that everything starts again from t = 0 and theta = 0. Note that theta = 0 places the initial point on the positive x axis, since angles are measured counterclockwise from that axis.
Time to the nearest second how long it takes the point to move all the way around the circle. How is this time related to the angular frequency?

Drag the mouse across the Radius box and change the radius to 1.5. Similarly change the theta0 box to 3.14, approximately equal to pi radians. And change the ang freq box to 1.
Click on Run Simulation again. Note how the simulation starts at the theta = pi point (the leftmost point on the circle, as opposed to the rightmost point as in previous runs). Note also how the time required to complete a trip around the circle is increased, due to the decreased angular frequency. You will naturally have notices the effect of the increased radius.

Now you will change radius and angular frequency using just the mouse. First click on the button labeled 'increment 1.000'. Note the angular frequency in the ang freq box, and eyeball the speed of the point as it moves around the circle. Then click on the 'incr freq' button and see what happens to the motion of the point and to the angular frequency displayed in the ang freq box.
Now note the radius, which should at this point be 1.5, then click on the 'decr rad' button. The effect should be obvious.
Using the buttons increase the frequency to 2.3 rad/s (click on the 'increment 0.100' button then click three times on the 'incr freq' button. Then achieve a frequency of 2.284 rad/s.
Similarly, change the radius to 1.794.
What do you think is the smallest change you can detect in the angular frequency of the motion? What about radius?

Set the radius to 1 and angular frequency to 2 and again click on Run Simulation. Then increase the radius to 2. Note how an increased radius increases the actual speed of the point on the circle, even though the simulation itself doesn't appear to be moving any faster.

You should now be able to use the program to run the experiment.