To investigate how the size of a parachute effects acceleration of the blutac attached to the parachute.

Investigating the effects of forces and acceleration

Aim

Information I already know

The bigger the surface area of the parachute the more the air resistance builds up underneath the parachute, which causes it to float gently to the ground.

Safety

To get to a sufficient height I must stand upon a table, to make this experiment safe I will make sure not to fall, as this would cause harm to myself and the people around me.

Apparatus

String

Paper

Blutac

Scissors

Sellotape

Stopwatch

Fair test

To make my experiment fair I will drop the parachute from the same height each time, keep the weight of the blutac the same and place the blutac in the same position on the string each time. If I were to change any of these it would make an error in the results.

Measurements

I plan to use three parachutes in this experiment; the first one will be 10cm by 10cm, the next 15cm by 15cm and the last to be 20cm by 20cm. The pieces of string on each of the corners of the parachute will all be the same for each parachute, the string will be 15cm.

Method

This is a preview of the whole essay

Measurements

Method

The first thing I plan to do in my experiment is to make all three of the parachutes, each of them will be the same shape (square) then I will attach the four pieces of string to the four corners with sellotape. I will make sure that the pieces of string are in the same pace on each corner and the same place on each parachute. I will then attach the weight (the blutac) onto the end if the string joining all four pieces together. Then drop from a height of 2m, I will then time from when I drop the parachute to when the parachute lands to get the time of the acceleration of the parachute. As it is very difficult to time exactly when the parachute was dropped and landed I will repeat this ten times and then work out an average. This will make my results more accurate. I will repeat this again with the parachute that is 15cm by 15cm and then the same with the 20cm by 20cm.

Prediction

I predict that when I do my experiment the bigger the surface area of he parachute the longer the parachute will take to reach the ground. I think this because the bigger the parachute the more air resistance there is underneath the parachute and it’s the air resistance, which keeps the parachute in the air. The bigger the air resistance the quicker the terminal speed is reached. The terminal speed is when the force acting down an object (gravity) is equal to the force acting up on the object (air resistance.) The terminal speed of an object is what speed the object is falling down all and all through an objects decent it is quickening (until it reaches it terminal speed. The quicker it reaches its terminal speed, the slower the object will descend.

Results

Averages

10cm by 10cm = 0.10

15cm by 15cm = 1.30

20cm by 20cm = 2.0

Evaluation

When I did this experiment the method I se worked really well and I didn’t do anything different than what I wrote in my plan. I believe that my results are accurate as I tried to make my experiment as fair as possible by timing the parachutes ten times so that I could get an average as this helps to make sure the results are as accurate as possible as this is supposed to take out any timing errors that I was sure to get as it was very difficult to time the parachute completely accurately. I also used the same weight and the same pieces of string on each parachute. I made sure I sellotaped the pieces of string in the same place on each parachute as that could also affect my results if I didn’t do this.

If I were to do this experiment again I could improve it by dropping each parachute more than ten times to make my results that more accurate.

I could extend my investigating further by making more parachutes and trying different materials. I could also do an investigation using the same sized parachute but change the weight each time, this would tell me the relationship between the force and the weight.