I finally understand error.... and not in the way that you may think...

Below is the set up that I used for the procedure I am talking about:

Recently, in my Physics class, my teacher, whom I have interviewed, pulled me aside to show me something magnificent.

We began with an air track and a gate in which it measure the speed that a sled flies through it. I will provide a picture above to make more sense. We began measuring different speeds that the sled was going through the gate. I only recorded numbers in the 90's. Interestingly, I saw that numbers repeated. Specifically, 92.5, 93.4, and 94.3 centimeters per second. This got me thinking, why does the clock do this?

The tool measures the speed to the nearest tenth of a centimeter, which is pretty precise. Dr. Voss then explained to me this; there is a clock within the measuring tool. Almost like a frame rate in which the tool measures the speed. Between 94.3 and 93.4 there is 0.9cm/s.

Let t=time.

92.5=1/t_1(s) 93.4=1/t_2(s) 94.3=t_3(s)

1/92.5=t_1 1/93.4=t_2 1/94.3=t_3

t_1=0.0001 t_2=0.0001 t_3=0.0001

The clock measures at 0.0001 second intervals.

Why is this so important? Because there are certain numbers that you will never be able to get. You will never be able to measure 94.4 and 94.2, you will only get 94.3.

This makes me wonder, what about space exploration? How precise are the measuring tools that engineers and physicists use on a daily basis? Even just a small error could throw off an entire mission. I have noticed in my previous procedures that a small error has affected my outcome greatly, so what about the rovers, spacecrafts, and satellites in space?

I think part of it is recognizing that there is error and that there is a possibility for a sudden need for change. Engineers and physicists probably account for that error by programming different trajectories and understanding the scope of where the spacecraft or celestial body may go, because numbers are so infinite that precision is difficult to achieve.

All in all, it is interesting to understand how error can affect a larger scale project in the long term and how precision is an incredibly difficult thing to achieve.

-Bailley G

Sources:

The Lawrenceville School Physics Lab

These calculations: