Two track problem
From Algodoo
Two track problem
| Language: | English |
|---|---|
| Description: | This problem explores the behaviour of two objects rolling on different tracks. How does the shape of the track influence the motion of the balls? The slope causes a gain in speed which will give a higher average speed through the track. The example illustrates how a change in direction means acceleration. It is also possible to discuss how speed and acceleration can be broken up into compo- nents parallel and vertical to the ground. |
| Target: | Key Stage 3 |
| Category: | Exercise, Laboratory |
| Discipline: | Static forces, Gravity, Motion |
| Learning objectives: |
|
| In class: | Draw the problem on the whiteboard and ask the students which one of the balls reaches the end of the track first. Discuss different aspects of what might influence the motion.
Discuss how this can be visualized and explored in Algodoo. Let the students create scenes in Algodoo using the suggestions you came up with together or let them use their own ideas. Help the students make decisions and ask guiding questions. Encourage the students to follow the procedure Create – Predict – Interact – evaluate. Allow the students to follow-up and share their experiences in class after the simulation. |
Steps in Algodoo
Create a scene
Make the two tracks using rectangular boxes. Try to make smooth transitions in order to prevent bouncing. Assign steel to the balls and set the restitution to zero in order to prevent bouncing of the balls.
Make a prediction
Which boll reaches the end of its track first?
Run/interact
Collect the bets and start the simulation and watch the ball roll on the two tracks. Note: Run the simulation without velocity representation first.
Evaluate
How can we explain that the ball that roll the longest way reaches the finish first? Discuss changes in velocity. In which places do we have acceleration and how does that affect the motion?
Run/interact
Run the simulation again and use velocity vector representation to discuss how the box is gaining speed in the slope.
Evaluate
Which type of track is fastest? Is a straight track always slower than an up-and-down- track? Make different tracks to check different hypothesis. Measure the speed of the ball at different places on both tracks and calculate the average speeds.
