For a barometer, why does the mercury rise into the tube?

Question

I want the specifics. Like is it because the tube contains vacuum, and do balance the atm. pressure, it will rise?

Answer 1

You seem to have the right idea.

There is a vacuum above the column of mercury, so there is no pressure pushing it down.

Meanwhile, there is atmospheric pressure pushing against the reservoir of mercury, which is connected to the mercury in the tube. So that amount of pressure is pushing the mercury up.

The difference between atmospheric pressure and zero pressure (the vacuum) is counteracted by the weight of the column of mercury, specifically, the weight of the mercury that is above the level of the reservoir.

Answer 2

Barometer (b?r?m'?t?r) , tool for measuring atmospheric rigidity. It replaced into invented in 1643 by way of the Italian scientist Evangelista Torricelli, who used a column of water in a tube 34 feet (10.4 m) long. This inconvenient water column replaced into quickly replaced by way of mercury, that's denser than water and demands a tube approximately 3 feet (0.9 m) long. The mercurial barometer includes a tumbler tube, sealed at one end and crammed with organic mercury. After being heated to expel the air, that's inverted in a small cup of mercury noted as the cistern. The mercury interior the tube sinks quite, turning out to be above it a vacuum (the Torricellian vacuum). Atmospheric rigidity on the exterior of the mercury interior the cistern helps the column interior the tube, which varies in height with adjustments in atmospheric rigidity and subsequently with alterations in elevation, many times lowering with will strengthen in height above sea point. standard sea-point rigidity is 14.7 lb according to squarein. (a million,030 grams according to squarecm), that's resembling a column of mercury 29.ninety two in. (760 mm) in height; the shrink with elevation is approximately a million in. (2.5 cm) for each 900 feet (270 m) of ascent. In climate forecasting, barometric readings are commonly measured on electronically controlled gadgets commonly tied to computers. the outcomes are plotted on base maps so as that analyses of climate-generating rigidity structures could be made. At a given area a typhoon is regularly predicted while the barometer is falling quickly; while the barometer is turning out to be, honest climate could commonly be predicted. The aneroid barometer is a steel container so made that when the air has been partly removed from the container the exterior depresses or expands with version of air rigidity on it; this action is transmitted by way of a practice of levers to a pointer which shows the rigidity on a graduated scale. A barograph is a self-recording aneroid barometer; an altimeter is often an aneroid barometer used to calculate altitude..