Tag: physics

Evaporization is the vaporization process of converting the liquid phase to vapour phase when surrounding temperature is more than liquid / water temperature.

Evaporation is a surface phenomenon.
Particles present on the surface of a liquid only face attraction from one side (the side containing fluid particles) and surface tension. Where as particles inside the liquid would face attractive forces from all around, making it difficult for such particles to evaporate or escape.
Hence the statement is true, explanation is true and the explanation is the correct explanation for the statement.

A: At room temperature evaporation of ethanol is rapid as compared to water. Hence, A is incorrect. 

 pressure at a point in a fluid is = $\rho gh $ where $\rho$ is the density of the liquid , h is the height or depth of the object from the surface , so pressure increases with increase in depth so given statement is false .

 1 atm = 1 pa = 76 cm of Hg 

Pressure exerted sideways is known as  lateral pressure  , hence the given statement is true so option (A) is correct

With the increase in the weight of an object the pressure increases because pressure is thrust per unit area.

$Load=900 kgf, Effort (E)=?$
Area of cross section of the press plunger $=a _1=9 m^2$
Area of cross - section of the pump plunger $=a _2=0.03 m^2$
By Pascal's law,
Pressure exerted by pump plunger $=$ pressure exerted on press plunger.
i.e., $\displaystyle \frac {L}{E}=\frac {a _1}{a _2}\Rightarrow \frac {900 kgf}{E}=\frac {9 m^2}{0.03 m^2}$
$\displaystyle \Rightarrow E=\frac {900 kgf\times 0.03 m^2}{9 m^2}=3 kgf$.

Force $(F)=500000 N$
$Pressure=250000 Pa, Area (A)=?$
$A=\frac {F}{P}=\frac {500000}{2500000}m^2=0.2m^2$.

To maintain normal atmospheric pressure below sealevel, deep seadivers wear a special suit.