prep 2 , unit 2

The height of atmospheric envelope is about above sea level.

• 1000 km

• 1000 m

• 1000 mbar

• 13 km

Atmospheric pressure is the...... of air column of an atmospheric height on a unit area.

• mass

• volume

• weight

• density

The measuring unit of atmospheric pressure is.........

• bar.

• Newton.

• millimetre.

• millilitre.

A device that is used in measuring the atmospheric pressure is. ..........

• barometer.

• voltmeter.

• ammeter.

• speedometer.

The normal atmospheric pressure equals.......... mbar at sea level.

• 76

• 1013.25

• 1.013

• 760

As the density of air increases, the atmospheric pressure...........

• increases.

• decreases.

• doesn't change.

• doesn't affect.

........... is an instrument used by pilots in aeroplanes to measure their elevation above sea level based on atmospheric pressure.

• Altimeter

• Thermometer

• Aneroid

• Digital balance

The amount of change in the temperature at any height in troposphere is given by...

• height in metres x 6.5

• height in km ÷ 6.5

• height in km + 6.5

• height in km × 6.5

Temperature decreases by.......... at 2 km above sea level.

• 65 deg * C

• 13 deg * C

• 5.6 deg * C

• 9.75 deg * C

All the atmospheric phenomena on the Earth like rains, winds and clouds take place in .......layer.

• mesosphere

• stratosphere

• thermosphere

• troposphere