I predict that as the surface area of the canopy increases, the time it takes for the parachute to fall also increases. This is because the air resistance is larger, therefore the drag is increased. So the speed of the parachute decreases. This is because the forces (air resistance and gravity) are unbalanced. The change in air resistance is important because the larger the surface area of the canopy, the more air particles it is ‘hitting’; therefore the air resistance is bigger.
In our investigation, the variable that we changed (the independent variable) was the surface area of the canopy of our parachutes. The result that we measured (the dependent variable) is the time taken for the parachutes to fall to the ground. The controlled variables were the altitude of the fall (height from which we dropped the parachute) and the weight and size of the plasticine. This is shown in the table below. Variable| Control|
Height from which we dropped the parachute| * This was to make sure the parachutes fell from the same distance. * We did this by using the same balcony.| Weight of the Plasticine| * This was to make sure only the area of the canopy affected the speed of the parachute. * We did this by weighing our plasticine on a scale.| Shape of Plasticine| * This was to make sure only the area of the canopy affected the speed of the parachute. * (Galileo’s Law of Falling Bodies states that the shape of an object affected the speed of a fall.) * We did this by creating identical balls of plasticine| The length of the rubber bands| * This was to make sure that only the area of the canopy affected the speed of the parachute. * We did this by using the same sized rubber bands, then cutting them, ensuring that they would be the same length.|
1) Create canopies by cutting squares out of plastic bags, using a ruler...