# Usiing angles and height to calculate height/altitude of object

1. Mar 16, 2012

### moonman239

Pre-requisite: Protractor
Requirement: Both the measurers and the object should be perpendicular to the ground

One-Person Method: Find point A, the point whose vertical distance to the ground you want to measure. If you're measuring the height of an object, this will be the top of the object. If you're measuring the altitude of the object, this will be the bottom of the object.Measure the angle of elevation from your head to point a. Call that angle A. Then measure the angle of elevation from the bottom of your feet to the top of the object. Call that angle B.

The first thing to do is calculate d, the horizontal distance between you and the object. d = your height / ((tan(A) - tan(B)).
Then use trigonometry to solve for h, the distance from point a to the ground. (If you want to know the height of an object - as in the distance between the top of the object to the bottom - and the bottom is higher than your feet - you'll need to subtract the vertical distance from the top of the object to the ground from the vertical distance from the bottom of the object to the ground.) Since tan(A) = h/d, d*tan(A) = h.