Answer to Question #303175 in Molecular Physics | Thermodynamics for Dhanush

Question

Define viscosity discuss the effect of temperature and pressure on viscosity a

Answer 1

Viscosity is a variables that describes a fluid resistant to flow.

Effect of temperature on viscosity

In case liquid , when temperature of liquid is increased the cohesive force i.e the intermolecular forces of attraction between the molecules is decreased due to which the viscosity of liquid is decreased.

In case of gas, when the temperature of gas is increased the kinetic energy of molecule is increased , molecular momentum of gas molecules is increased due to which viscosity of gas molecules is increased

Effect of viscosity on pressure

In case of liquid, viscosity of liquid is increased when pressure of liquid is increased except water.

In case of gas, viscosity of gas is independent on pressure