Friction is hard to visualise and quantify in textbook scenarios. Using iPad sensors helps to collect real-time data that can be analysed by students.
Preparation & Flow
Introduction and Set-up (10 mins)
Teachers should recap concepts related to resultant force, friction, and acceleration.
Each group gets a small, wheeled toy (can also be a car, robot, or ball). They should prepare ramps with different surfaces (sandpaper, cloth, plastic).
Teachers should ask students to predict the shapes of graphs of “Surface type against speed” and “Force against acceleration” prior to conducting the race.
The Race (20 mins)
Measure acceleration and time using PhyPhox’s “acceleration” or “timing gates” functions.
Repeat the race until sufficient data is collected. At this juncture, teachers should also emphasise the importance of repeated data collection as an essential skill in a Physics Lab environment.
Data Analysis (20 mins)
Enter data into Numbers to plot graphs of:
Surface type against speed
Force against acceleration
Class Discussion (10 mins)
Debrief: how does surface affect net force? When does air resistance start to matter?
Possible Extensions
Design Challenge: Design a “low-friction” car race for the next lesson.
From the LearnGrowCreate Team
Main author: Sharon
Attach up to 5 files which will be available for other members to download.