Falling ball

Research question (what will you be investigating in your experiment? Be specific!):

How does the deformation of gel changes related with the energy that has the ball when it falls?

Hypothesis (your answer to the above question and the scientific explanation to it):

I think that the higher is the ball, the more that will be affected the gel. Because the higher the ball is the more mechanical energy has and the faster it will reach the floor. Mechanical energy is formed with two main components: potential energy and kinetic energy. The mechanical energy will maintain because the potential energy converts into kinetic energy. Potential energy (mass*high*gravity) depend of the high and the kinetic energy (1/2 * mass * velocity ²) so therefore, when we drop the ball from the different highs those balls will have different potential energy that will be transformed into kinetic and therefore into different velocities.  The highest the place from where you throw the ball is the fastest that is the final velocity. So the impact will be bigger, so the deformation will be more notable.

(Physicsclassroom.com, 2014)

List of variables (including the way of measuring or controlling them):

        

Independent variable (what you will change): heights ( 2m, 4.43m, 7m, 10.77m and 13.89m)

(I will measure it and control it with a tape measure and control it because we will throw the ball from the bannisters)

        

Dependent variable (what you will measure): deformation (deep) of the gel

(I will measure it in centimeters with a ruler; once the ball has fallen I will take it off and introduce the ruler to see the amount of cm. that has been introduced)

        

Controlled variables (what will you keep the same): weight of the ball, pressure, temperature, amount of gel and that the initial velocity is cero. (I will measure the weight of the ball with a scale, the pressure with a barometer and the temperature with a thermometer, the amount of gel with a ruler and the scale)

List of materials:

• Meter
• Ball
• Gel
• Ruler
• Thermometer
• Barometer
• Weight / balance

Method:

1. We weigh the ball (this is for measuring the velocity, optionally)
2. We measure the different height with a tape measure.
3. We drop the ball from the different height three times over a piece of gel that needs to be all the same (weight, shape…)
4. We measure the centimeters of deformation of the gel. (with the ruler)
5. We calculate the average with a calculator.
6. We make the graph in excel.
7. We make a conclusion and compare it with the hypothesis.

Falling wood ball into the gel:

Table for results (include a blank table that you will use to record data):

Depth (Cm) of penetration of the ball to the gel

Height (m) from where the ball has been dropped	First time	Second time	Third time	Fourth time	Fifth time	Average
2	2,5	2,4	2,6	2,5	2,3	2,46
4,43	4,2	3,9	4,6	4,4	3,7	4,16
7	5,5	6	5,3	5,7	5	5,5
10,77	7	6,8	7,3	7,5	7	7,12
13,89	8,7	8,9	8,7	8,5	8,5	8,66

Bibliography:

Physicsclassroom.com. 2014. Mechanical Energy. [online] Available at: http://www.physicsclassroom.com/class/energy/u5l1d.cfm [Accessed: 24 Jan 2014].

Centros5.pntic.mec.es, (2014). Ca�da libre. El rinc�n de la Ciencia. [online] Available at: http://centros5.pntic.mec.es/ies.victoria.kent/Rincon-C/Alumnos/al-25/al-25.htm [Accessed 13 May. 2014].