Advertisements
Advertisements
प्रश्न
The force of viscosity is
विकल्प
electromagnetic
gravitational
nuclear
weak
Advertisements
उत्तर
The force of viscosity arises from molecular interaction between different layers of fluids that are in motion. Molecular forces are electromagnetic in nature. Therefore, viscosity must also be electromagnetic.
APPEARS IN
संबंधित प्रश्न
The viscous force acting between two layers of a liquid is given by \[\frac{F}{A} = - \eta\frac{dv}{dz}\]. This F/A may be called
Water flows at a speed of 6 cm s−1 through a tube of radius 1 cm. Coefficient of viscosity of water at room temperature is 0.01 poise. Calculate the Reynolds number. Is it a steady flow?
The unit of viscosity is
In a horizontal pipe of non-uniform cross-section, water flows with a velocity of 1 ms−1 at a point where the diameter of the pipe is 20 cm. The velocity of water (1.5 ms−1) at a point where the diameter of the pipe is (in cm)
What is Reynold’s number? Give its significance.
Derive Poiseuille’s formula for the volume of a liquid flowing per second through a pipe under streamlined flow.
A small metal sphere of mass M and density d1, when dropped in a jar filled with liquid moves with terminal velocity after sometime. The viscous force acting on the sphere is (d2 = density of liquid and g = gravitational acceleration)
An incompressible liquid flows through a unifonn cross sectional tube with velocity 20 cm/s. If the thickness of liquid layer is 0.8 cm then velocity of gradient of flow is ____________.
The tangential force or viscous drag on any layer of the liquid is directly proportional to the velocity gradient `"dv"/"dx"`. Then the direction of dx velocity gradient is ____________.
In motors, more viscous oil is used in summer than in winter due to ____________.
The velocity of water in river is 8 km/hr of the upper surface. The river is 12 m deep. If the coefficient of viscosity of water is 10-2 poise then the shearing stress between horizontal layers of water is ______.
Clouds float in the air due to ______.
The velocity of a small ball of mass M and density d, when dropped in a container filled with glycerine becomes constant after some time. If the density of glycerine is `"d"/2`, then the viscous force acting on the ball will be ______
The coefficient of apparent expansion of mercury in a glass vessel is 153 × 10-6/°C and in a steel vessel is 144 × 10-6/°C. If α for steel is 12 × 10-6/°C, then that of glass is ______.
An incompressible liquid is flowing through a uniform cross-sectional tube with a velocity 12 cm/ s. If the thickness of liquid layer is 0.8 cm, what is the velocity gradient of that flow of liquid?
The dimensions of coefficient of viscosity are ______.
A water pipe with diameter of 5.0 cm is connected to another pipe of diameter 2.5 cm. How would the speeds of the water flow compare?
