1.18 describe experiments to investigate the forces acting on falling objects, such as sycamore seeds or parachutes
Experiment: Measuring the force of a falling ball using light gate
Apparatus required: Cylinder, light gate, data logger, electric balance
First, we measure the weight of the ball using an electric balance. This is the force acting downwards all the time.
Set up the cylinder using light gate at different points keeping the same distance difference between each of them. Fill the cylinder with oil or any other liquid. For more accurate results, we will be using a cylinder with a diameter close to the diameter of the ball.
Now release the ball from the top of the cylinder. After it reaches the bottom, we will notice that the time taken between each light gates increases as it go downwards. We can calculate the acceleration from that. Since, F = ma, we can calculate the resultant force.
That means, the resistance acting on the increases. At a time, the resistance will equal the weight, and the forces will be balanced. It will then fall with a constant velocity.