Advertisements
Advertisements
Question
Toricelli’s barometer used mercury. Pascal duplicated it using French wine of density 984 kg m–3. Determine the height of the wine column for normal atmospheric pressure.
Advertisements
Solution 1
10.5 m
Density of mercury, ρ1 = 13.6 × 103 kg/m3
Height of the mercury column, h1 = 0.76 m
Density of French wine, ρ2 = 984 kg/m3
Height of the French wine column = h2
Acceleration due to gravity, g = 9.8 m/s2
The pressure in both the columns is equal, i.e.,
Pressure in the mercury column = Pressure in the French wine column
`rho_1h_1g = rho_2h_2g`
`h_2 = (rho_1h_1)/rho_2`
`= (13.6xx10^3xx0.76)/984`
= 10.5 m
Hence, the height of the French wine column for normal atmospheric pressure is 10.5 m
Solution 2
We know that atmospheric pressure, `P = 1.01 xx 10^5 "Pa"`
If we use French wine of density, `rho= 984 kg m^(-3)`, then height of wine column should be
`h_(m')` such that `p = hrhog`
`=> h_m = P/(rhog) = (1.01xx10^5)/(984xx9.8) = 10.47m ~~10.5 m`
RELATED QUESTIONS
A 50 kg girl wearing high heel shoes balances on a single heel. The heel is circular with a diameter 1.0 cm. What is the pressure exerted by the heel on the horizontal floor?
For a given thrust, pressure is more on a surface of large j area.
State the unit of thrust
When does a man exert more pressure on the floor: while standing or while walking?
A gum bottle rests on its base. If it is placed upside down, how does the thrust change?
A normal force of 200 N acts on an area of 0.02 m2. Find the pressure in pascal.
Find the area of a body which experiences a pressure of 50000 Pa by a thrust of 100 N?
A boy weighing 60 kgf stands on platform of dimensions 2.5 cm x 0.5 cm. What pressure in pascal does he exert?
The pressure in a liquid at two points in the same horizontal plane are equal. Consider an elevator accelerating upward and a car accelerating on a horizontal road. The above statement is correct in
Water flows through a horizontal tube of variable cross section. The area of cross section at A and B are 4 mm2 and 2 mm2 respectively. If 1 cc of water enters per second through A, find (a) the speed of water at A, (b) the speed of water at B and (c) the pressure difference PA − PB.
Consider the statement given below and choose the correct option.
Assertion: Broad straps are used in bags.
Reason: Broad straps last for long.
A water tank has four taps fixed at points A, B, C, D as shown in the following figure. The water will flow out at the same pressure from taps at
A chapatti maker is a machine which converts balls of dough into chapatties. What effect of force comes into play in this process?
Assertion: The pressure at the bottom of the sea is lesser than that near the surface.
Reason: The pressure exerted by a liquid depends upon the depth of the liquid and density of the liquid.
Give reasons why:
cutting edges of knives and axes are sharpened.
In petrol bunks, in what unit is tire pressure measured?
Fluids in general are ______.
Scuba divers wear special suits to withstand ______.
It is easy to compress a gas whereas liquids are ______.
Pressure is a scalar quantity because ______.
- it is the ratio of force to area and both force and area are vectors.
- it is the ratio of the magnitude of the force to area.
- it is the ratio of the component of the force normal to the area.
- it does not depend on the size of the area chosen.
