Month: November 2013

Last friday, I was able to participate in two different experiments: the air power balloon and another one called “a battery that makes cents.”

The air power balloon experiment was very interesting. You could actually comprehend and understand the logic behind the experiment as you’re doing it. First, I had to blow into the balloon to verify it had a good quality. Secondly, I had to insert a straw into to the balloon and tape the ends so that no air would come out as I blow into the straw to fill the balloon. Shakyves, the chair of that team, build a car made of syrofoam; and the wheels were build nicely and intelligently enough to avoid any kind of friction. Finally, he attached the straw with the ballon at the end to the car, with the ballon (not yet filled with air) facing the back of the car. Here’s the experiment. For the first time, I just had to blow into the straw, fill up the balloon and hold the end to prevent the air from fleeing the balloon; at Shakyves mark, I then release the straw, and the car moved all the way down to the table. The second time I had to re-do the same thing but with a weight on top of the car; and the goal was to see how the speed and the distance travelled would differ. Here are the data:

*The area of the straw 0.007m  A=pi*r2 A=3.14*0.0035m2=0.0000385m 

-Test 1. No weight

.83s   4.36/5= .87s  120cm/.87s= 137.93cm/s2

-Test 2, adding 20g to it 

1.41s     7.13s/5=1.43s 120cm/1.43s=83.91cm/s2.

My other experiment was “the battery that makes cents” which according to the team, was a title made from a joke, explaining how it makes actual sense to use “cents” to create voltage. It was more of “watch and learn” type of experiment then the first one. They had a multimeter, with to electrodes, aluminum paper in which they had a pile of cents (nickel and pennies separated by pieces of paper previously immersed into a solution of vinegar and salt). Apparently, Vinegar was the electrolyte and salt that contains NaCl was the key to the relation between the cents and the solution. Indeed, nickels have Zinc in them which are charged negatively and pennies have Copper, which are charged positively. Therefore, the Na+ goes to Cu (copper) and the Cl- goes to Zn (zinc). Here are the datas in Volts:

130  – 340  –  480  –  560 .