To estimate the height of the trees we will first calculate the length of your pace.  To do this, you will lay out a tape measure and count the number of paces it takes you to walk the distance of the tape.  You should do at least three trials and take the average number of paces.  A pace is defined as two steps.  So if you start with your left foot  then you count "one" when you step with your right foot.  Your gait should be natural and not exaggerated.  Once you have the number of paces determined for a set distance you can calculate how many meters 1 pace is for you.

 

Once your pace has been determined, start with your back to the tree and walk a distance away from the tree that is approximately 1.5 to 2 times longer than the perceived height of the tree.  Count your paces as you go.  Make sure you end your pace at a location where you can see the top of the tree.  From this point,  you will use an inclinometer to measure the angle between horizontal and the top of the tree.  With the angle and pace (converted to meters), the height of the tree can be calculated using a simple trigonometric function.

 

Your pre-lab exercise is to draw a careful and detailed diagram of the tree height problem and derive the equation that will allow you to figure out the height of the tree.