Physics
Answer
An altimeter is an aneroid barometer, and it is used in aircraft to measure it's altitude.
It's principle is as follows —
As atmospheric pressure decreases with the increase in height above the sea level, therefore a barometer which measures the atmospheric pressure, can be used to determine the altitude of a place above the sea level.
It's scale is calibrated in terms of height of ascent with height increasing towards left because the atmospheric pressure decreases with increase of height above the sea level.
Related Questions
Mention two demerits of a simple barometer and state how they are removed in a Fortin barometer.
What is a barometer? How is a simple barometer constructed?
What is an aneroid barometer? Draw a neat and labelled diagram to explain its construction and working.
Draw a simple labelled diagram of a Fortin barometer and state how it is used to measure the atmospheric pressure.