First, you have to make sure you're measuring the right thing. Tilt isn't specific enough. You'll want to measure pitch and / or roll.
Make sure your accelerometer is capable of measuring tilt. Read the datasheets carefully. For example, the ADXL322 is a 2-axis accelerometer which is capable of measuring tilt. The ADXL78 does not repeat NOT have this in the datasheet. You could try to use the 78, but it might not work at all.
You must mount the accelerometer so that the sensitive edges are parallel to the ground. In other words, it has to be lying flat on its back. ("How flat?" It must be as flat as you want your accuracy to be. ) In such a configuration, the chip listed above will give pitch as pitch = arcsin( Ax / 1g) and roll as roll = arcsin( Ay / 1g ). Ax and Ay are the two outputs. Read the datasheet. (I can't stress this enough.)
While you would usually put the - and + outputs into an instrumentation amplifier, the 322 chip listed above does not have such a thing. You would have to run it through some kind of gain circuit, and probably one with an adjustable gain and offset.
Use a protractor.
It depends on the angle not all obtuse angles measure the same. To measure an angle you use a protractor.
A protracter
protracter
use a protractor
Acceleration is measured using an instrument called an ACCELEROMETER The simplest home-made accelerometer is a liquid-surface accelerometer, with water in a transparent liquid container with boxy sides. The slope of the liquid surface is a measurement of acceleration.
If you absolutely needed to measure an angle to find out its degree measure, you would use a protractor.
Use a protractor.
A protractor
Use a protractor.
It depends on the angle not all obtuse angles measure the same. To measure an angle you use a protractor.
put the protractor on the vertex and look up at the degree's and look belowacute angle =has a measure between 0 degree's and 90 degree'sright angle =has a measure of 90 degree'sobtuse angle = has a measure between 90 degree's and 180 degree'sstraight angle = has a measure of 180 degree'sthat's how you use a protractor to measure angles.
Use a protractor.
a protractor
Use a protractor.
A protractor.
A protracter