Home
Class 11
PHYSICS
Explain with the help of Bernoulli's pri...

Explain with the help of Bernoulli's principle that why does a spinning ball follows a curve path during flight ?

Text Solution

Verified by Experts

(i) Ball moving withou spin :

Streamlines for a fluid around non - spin ball
In above fihure , the streamlines around a non - spinning ball moving relative to the fluid.
It is clear that the velocity of fluid (air) above and below the ball at corresponding points is the same resulting in zero pressure difference.
Air therefore , exerts no upward or downward force on the ball .
Ball moving with spin : As a result there is an upward force resulting in a dynamic lift of the wings .

In above figure a spinning ball is shown .
A spinning ball drags air along with it.
If surface is rough more air drags.
The crowding of streamlines ay above the ball indicates high velocity and low pressure , while the sparse streamlines below the ball indicates low velocity and high pressure.
Thus difference in velocities of air results in the pressure difference between the lower and upper faces and there is a net upward force on the ball .
This dynamic lift due to spinning is called
Magnus effect.
Promotional Banner

Topper's Solved these Questions

  • MECHANICAL PROPERTIES OF FLUIDS

    KUMAR PRAKASHAN|Exercise SECTION-A Try Yourself (VSQs)|132 Videos
  • MECHANICAL PROPERTIES OF FLUIDS

    KUMAR PRAKASHAN|Exercise SECTION - B Numericals|29 Videos
  • MACHANICAL PROPERTIES OF SOLIDS

    KUMAR PRAKASHAN|Exercise QUESTION PAPER|11 Videos
  • MOTION IN A STRAIGHT LINE

    KUMAR PRAKASHAN|Exercise QUESTION PAPER|11 Videos

Similar Questions

Explore conceptually related problems

Explain blood flow and heart attack with the help of Bernoulli's principle.

Why does the water rise in a capillary tube Explain .

The lens governing the behavior of the rays namely rectilinear propagation laws of reflection and refraction can be summarised in one fundamental law known as Fermat's principle. According to this principle a ray of light travels from one point to another such that the time taken is at a stationary value (maximum or minimum). if c is the velocity of light in a vacuum the velocity in a medium of refractive index mu is (c)/(mu) hence time taken to travel a distance l is (mul)/(c) if the light passes through a number of media, the total time taken is ((1)/(c))summul or (1)/(c)intmudl if refractive index varies continuously. Now summul is the total path, so that fermat's principle states that the path of a ray is such that the optical path in at a stationary value. this principle is obviously in agreement with the fact that the ray are straight lines i a homogenous isotropic medium. it is found that it also agrees with the classical laws of reflection and refraction. Q. The optical length followed by ray from point A to B given that laws of reflection are obeyed as shown in figure is

(i) A poor emitter has a large reflectivity . Explain why. (ii) A copper tumbler feels much colder than a wooden block on a cold day. Explain why. (iii) The earth would become so cold that life is not possible on it in the absence of the atmosphere. Explain why? (iv) Why clear nights are cooler than cloudy nights? Why does a piece of red glass when heated and taken out glow with green light? (vi) Why does the earth not become as hot as the sun although it has been receiving heat from the sun for ages? (vii) Animals curl into a ball when they are very cool. Why? (viii) Heat is generated continuously in an electric heater but its temperature becomes constant after some time. Explain why? (ix) A piece of paper wrapped tightly on a wooden rod is observed to get charred quickly when held over a flame as compared to a similar piece of paper when wrapped on a brass rod. Explain why? (x) Liquid in a metallic pot boils quickly whose base is made black and rough than in a pot whose base is highly polished . Why?

Why Bernoulli's equation does not apply to unsteady or turbulent flow ?

Using the concept of evaporation explain why dogs pant during hot summer days? (AS_1)