1. Go to the website: phet.colorado.edu Click "Play with sims". Navigate to the "Physics" "Motion" section of the menu on the left side of the screen. Find the simulation "Motion in 2D". Run the simulator and play with it to familiarize yourself with its features. 2. Click the "Simple Harmonic" button. What shape is the ball's path? Sketch a graph of x vs. t for the ball. 3. Is the ball moving with constant velocity? Sketch a graph of velocity vs. t for the ball. 4. Is the ball accelerating? Is the acceleration constant? 5. Click the "Show both" button. The simulator shows two vectors that represent the motion. One of the vectors is the ball's velocity and the other is the ball's acceleration. Is the green vector the velocity or the acceleration? Is the blue vector the velocity or the acceleration?

2. Go to the website: phet.colorado.edu Click "Play with sims". Navigate to the "Physics" "Motion" section of the menu on the left side of the screen. Find the simulation "Masses & Springs". Run the simulator and play with it to familiarize yourself with its features. 2. Hang one of the masses from spring 3. Use the slider on the right side of the screen to adjust the stiffness of spring 3. Does a "soft" spring have a large or small spring constant? 3. Disturb the mass so that it oscillates on the spring. Observe the frequency of the oscillatory motion when spring 3 is soft and hard. Is the frequency larger if the spring constant is large or small? 4. Sketch a predicted graph of frequency vs. spring constant for the cart shown in Fig. 1. 5. Hang the 50 g, 100 g, and 250 g masses from spring 2. Observe their oscillations. Is the frequency larger if the mass is large or small? 6. Sketch a predicted graph of frequency vs. mass for the cart shown in Fig. 1. 7. Sketch a predicted graph of frequency vs. amplitude for the cart shown in Fig. 1.