Why mercury is mostly used as a manometric fluid?
Mercury is a useful material to use in a manometer because of its high density. This means that a much shorter column is needed compared to water. For instance, the pressure represented by a column of 100 mm of water is just under 7.4 mm of mercury (mmHg).
Why is mercury used as barometric liquid Give two reasons?
Two advantages of using mercury as barometric liquid: (i) The density of mercury is greater than that of all the liquids, so only 0.76m height of mercury column is needed to balance the normal atmospheric pressure. (ii) The mercury neither wets nor sticks to the glass tube therefore it gives the correct reading.
Why is mercury used instead of water in a thermometer?
We use mercury in thermometers because most metals are good conductor of heat and mercury is the only metal in liquid state. No,we cannot use water instead of mercury because water do not expand as per temperature given to it and can give us wrong reading.
Why is mercury used as thermometric liquid give three reasons?
Mercury is used as a thermometric liquid because: It has a lower freezing point (-39°C) and a high boiling point (35°C). It is shiny liquid metal, hence can be easily seen through the glass of the thermometer tube. It has a fairly large expansion for a small change in temperature.
Why do we use mercury as a fluid in thermometer and not water class 7?
Mercury is the only metal that is in liquid state at room temperature. It is used in thermometers because it has a high coefficient of expansion which makes it easy to move in the thermometers as per the temperatures. Mercury has a boiling point which makes it suitable to measure higher temperatures.
When to use red oil or mercury in a manometer?
Mercury is used when the measured fluid mixes with the manometer luid or a very long tube length is necessary, while red oil is used as the indicating fluid when it is required to read a manometer from a distant place. It is easier to read and it does not combine chemically with some fluid in a dry system.
What is the formula for Mercury in a manometer?
Mercury has a density much higher than that most of the working fluids, for which the pressure difference is to be measured. The formula used in case of a manometer is ∆P =[(Density of manometric fluid – Density of working fluid)×(height difference in level of manometric fluid in the two limbs)×g]
Why is Mercury preferred over water in a barometer?
Mercury has high density and low length is essential for pressure measuring. Its high density helps to make small manometers. It does not evaporate like water would, and its lower freezing point means it will not freeze up at 0 deg C. Simply it has compactness, visibility and stability. Besides, why is Mercury preferred over water in a barometer?
What kind of fluid can be used as a manometer?
Not necessarily mercury, any fluid having following four characteristics can be used as manometer fluids: It should not wet the wall of container and is free to move in limbs. It should not absorb gas, and is chemically inert.