Does the shape of a parachute change how fast it falls? You cut four shapes from plastic bags: a triangle, a square, a rectangle, and a circle. Each shape has the same surface area of 500 square centimeters. You attach strings and a small washer to each one.
An assistant drops each parachute from a second-floor balcony while you time the fall with a stopwatch. You divide the drop distance by the time to calculate the speed. The round parachute falls the slowest and the triangular one falls the fastest.
Hypothesis
The hypothesis is that among the parachutes, the round parachute will take the longest to land.
Shape affects how hard air pushes back on a falling object, even when the total surface area stays fixed. Cut four parachutes from plastic bags — a triangle, a square, a rectangle, and a circle — each at 500 square centimeters. Drop them from a second-floor balcony and time each fall. The round parachute catches more of the pushing force from the air and falls the slowest. The triangular one falls fastest.
Air pushes back harder on some shapes than others, even when the total surface area stays the same. Cut four parachutes from plastic bags — a triangle, a square, a rectangle, and a circle — each at 500 square centimeters. Attach strings and a small washer to each, then drop them from a second-floor balcony while timing each fall with a stopwatch. The round parachute falls the slowest. The triangular one falls the fastest. Same area, different shape — and the difference in that pushing-back force is clear in the data.
Method & Materials
You will cut shapes from plastic bags, punch holes in the corners, tie strings to the holes, and measure the drop speed of the parachutes.
You will need 4 plastic bags, 15 threads, 4 washers, a measuring tape, a stopwatch, an assistant, and a building with a balcony on its second floor.
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The results of the experiment showed that the round parachute took the longest amount of time to land and the triangular parachute took the least amount of time. The hypothesis holds true: among the parachutes, the round one took the longest amount of time to land.
Why do this project?
This science project is interesting because it explores the relationship between the shape of a parachute and its drop velocity. It also provides insight into how parachutes are used in military and cargo drops, as well as extreme sports.
Also Consider
Consider using parachutes that have different surface areas, or dropping the parachutes from different heights.
Full project details
Additional information and source material for this project are available below.
