Ok, This is more than likely a really basic question but. I need to know how I can discover out how huge a ball is. For example, a tennis ball is 2 1/2 inches big, yet how carry out you discover that?

Though, for reference, the explanation and answer come this question needs to be as basic as it have the right to possibly get. I have actually a learning special needs that greatly affects my invernessgangshow.netematics capabilities and severe Dyscalculia. This explanation right here probably renders me sound pretentious, yet a lot of of civilization don"t know or they throw too many numbers at me and get frustrated once I haven"t claimed anything before hand. I"m sorry if that does, however I"m spanning all mine bases lol.

Any aid on just how to number this question out is very much appreciated!

You are watching: How to measure diameter of a ball

inquiry Jun 19 "15 at 19:37

1311 silver- badge33 bronze badges
include a comment |

3 answer 3

active oldest Votes

See more: How To Tell If Lobster Is Bad ? How Can You Tell If A Cooked Lobster Is Bad

One easy method to measure up the "size" the a round is how far it is from next to side. Her tennis ball example is a great one: a typical tennis round is around 2.5 inches type side to side. And one method to measure that dimension is to location the sphere on a table in the sunlight as soon as the sun is virtually overhead -- close come noon.

The ball"s zero is then practically a circle, and you can measure the width of the circle with a ruler, and also that"ll it is in the width of the sphere as well.

Another way to measure this is to put the ball between two (large) books and also hold the publications parallel; it"s then easier to measure the distance in between the books with a ruler.

Finally, you have the right to wrap a string approximately the middle of the sphere -- the very widest part, choose wrapping approximately the equator of the earth -- and mark the string v a pen for this reason that between the two pen-marks is exactly one trip roughly the ball"s middle. Intend that this comes out to be 42 inch (which can happen for a kid"s kickball, for instance). If you division the size (42 inches) by the number 3.14, you get

42 / 3.14 = 13.38, more or less

and that tells you the the round is a little much more than 13 customs across.

The number 3.14 is one-of-a-kind -- it works no issue how large your ball is: you division the "length about the ball" by 3.14 and you gain the length throughout the ball. (The actual number is a tiny bit bigger than 3.14, however the distinction only matters when you"ll doing very specific things; 3.14 works for practically all handy purposes.)