Terminal velocity sim
Three forces act on the ball: its weight down, and upthrust and drag up.
Terminal velocity · covers the GCSE, IGCSE, O-Level topic
What the sim shows
Three forces act on the ball: its weight down, and upthrust and drag up. At first drag is small, so the ball speeds up; drag grows with speed until drag + upthrust = weight. Then the resultant force is zero, so there is no acceleration: the ball falls at a steady speed, its terminal velocity (6.4 cm/s for the 5 mm ball, 2.3 cm/s for the 3 mm one). In glycerol this happens within a few hundredths of a second, so the first band is placed below the surface; after that, each 5 cm gap takes the same time. Taking g = 10 m/s².
- The bands: 5 cm apart
- Right: speed against time, and the lap times
Use it in your lessons
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