Example - Space Needle

How tall is the Space Needle? Sure, The Google could tell you in an instant, but let's see what the Circuit Playground says.

First thing is to find a safe location with a good view. This street corner works.

Next we need to know the distance from here to the Space Needle. For this we will ask The Google for help. You can use Google Maps to measure the distance between two locations. Here are the steps used to determine the distance from the Space Needle to the street corner. This can be done for other locations as well.

Move mouse pointer to the location of the object (in this case, the Space Needle) and right click to bring up menu. Select Measure distance.

A small round circle will be placed to indicate the starting location. This can be relocated by grabbing and moving it with the mouse.

Click on the location where you are taking the angle measurement. A line will be drawn between the two points and the distance will be shown. Rounding to the nearest foot is fine, so in this case 780 ft.

Now we use our Circuit Playground inclinometer to measure the angle to the top of the Space Needle. Sight in the top through the plastic tube and press either button to take a measurement.

Here is the resulting display on the Circuit Playground. The green light on NeoPixel #9 means the reading is good, the #0, #2, and #5 NeoPixels are lit indicating the angle, and since the #8 NeoPixel is not lit, the value is positive.

Now we can use the worksheet to determine what angle is being indicated. In this case:

1 + 4 + 32 = 37 degrees

Then use a calculator to get the tangent of this angle:

tan (37 deg) = 0.7536

We determined our distance was 780 feet above, so just need to multiply to get the final answer:

780 x 0.7536 = 587.808

Let's just call it 588 feet.

The actual height of the Space Needle is 605 feet. So our reading was off by 17 feet. Oh well, not perfect, but not bad for a plastic straw and some rubber bands.

Last updated on 2017-11-17 at 12.55.59 PM Published on 2016-10-25 at 12.26.06 PM