One Million Pennies Project

By Philipp Angermair Block 4

Pennies vs. Cents

First of all, I had the problem that we did not have any pennies at home . Therefore, I decided to use 5-cent coins instead of pennies. Nevertheless, I will hereinafter only use the term “penny” for this presentation (although I actually measured the thickness of 5-cent coins and not of pennies). But pennies and 5-cent coins seem to have a similar thickness…

Next step was to make a stack of 10 pennies and I measured it with my ruler. And the answer was approximately 1.6 to 1.7 cm.

Then I also tried to measure the thickness of only one single penny and to multiply it by 10 but the result was not very precise…

Estimate, Measuring with Caliper

• The thickness of a stack of ten pennies (approximately 1.6 to 1.7 centimeters, measured with a ruler) was 3 to 4 millimeters more than I expected it to be. My guess was 1.3 centimeters . Thus, my guess underestimated the thickness of one coin and therefore also the height of the stack.

• Then I tried to find out, how I could come to a more precise measure and found out that there exists a special ruler, called “caliper” (in Austria we say “Schublehre “ or “Schiebelehre”) .

• Measuring the thickness of a stack of ten pennies with the caliper lead to a much more precise result of 16.84 millimeter (or 0.663 inches), which is equal to 1.684 centimeter.

First Estimates

• 1,000,000 pennies: First I thought that if you put one million pennies to a tower, it would reach to the moon.

• Then I asked my dad and he told me a tower with 1,000,000 pennies might even be higher than the highest building in Dubai and then I asked my mum and she said like the tower of St Stephens cathedral in Vienna. Finally, my sister said it might be as high as Big Ben in London.

The work to get my answer

• One million = 10 to the 6th power. • Since I measured the thickness of a stack of ten coins, I had

to multiply the result by 10 to the 5th power (= one hundred thousand).

• Therefore a scientist would write: 1.684 centimeter multiplied by 10 to the 5th power.

• As a decimal number that reads 168,400 centimeters • Which is equal to 1,684 meters (1 meter = 100 centimeter)• Which is approximately 1.7 kilometers (1 kilometer = 1000

meter)

Relations

• This picture shows the size of a 1,000,000 pennies-block compared with the size of a man.

• My first guess was that it would be much bigger, but one penny is just 1.684 millimeter thick. Therefore, it can’t be a tower to the moon…

Pennies in a line

• If ten pennies (again I used 5- cent coins for the measuring) were put next to each other in a line, the length I measured was 21.26 centimeter. Again I multiplied this result by 100.000. (1,000,000/10)

• 21.26 centimeter multiplied by 100.000 =2,126,000 centimeter, which is equal to 21,260 meter or approx. 21 kilometer.

Some related questions

• If you were able to stack one million pennies, one vertical ,one horizontal , and so on, how tall would it be ?

• The thickness of 10 pennies = 1.684 cm, the diameter of ten pennies = 21.26 cm. 1.684 + 21.26 = 22.944 cm multiplied by 50.000 = 1,147,200 cm, which is equal to 11,472 meter or approx. 11,5 kilometer

• How many Euro is one million 5-cent coins? (1 Euro = 100 cent):

• 1,000,000/100 = 10,000 multiplied by 5, therefore Euro 50,000.

Thank you

• I hope you liked my presentation and thank you for watching

• By Philipp Angermair