Category: Physics Notes PPT

It is relevant that atom is made up of nuclei and electron and it is bound by electromagnetic force and it is also known that mass of the electron is very small when compared to mass of nuclei( it consists of neutron and proton) and they ( electrons) are negatively charged and protons are present in point like quarks feature which are “up” and “down” in the nuclei.

According to the particle physics , it is stated that leptons are elementary particles with half integral spin(½) and it does not go under any strong interaction and it is divided into two branches that are:

1. Electrically charged lepton ( also called electron like lepton)

2. Neutrally  charged lepton ( also called neutrinos )

The charged leptons can combine with other particles to form composite particles such as atoms and positronium ( it is the reverse of electron it has the same mass but with a positive charge )while the neutrino rarely reacts with any other particle and they are rarely taken into observation and the best known lepton is electrons( electrons also have least mass of all charged leptons).

According to the above two classes it is divided into six types and grouped into three generation that are:

1. The first generation leptones are called electronic leptons which comprises of electron and electron neutrino 

2. The second generation leptons are called muonic leptones which comprises of muon and muon neutrino

3. The third generation leptons are called tauonic leptones which comprises of tau and tau neutrino 

The electric charge on the charged lepton is -1 e, 0 e , +1 e

History of Leptons

J.J Thomason with his team of british physicist in 1897 for the first time discovered electrons ( which was the first lepton to be discovered).

To preserve the conservation of energy, conservation of momentum and conservation of angular momentum in beta decay Wolf in 1930 gave its postulate for electron neutrino( in the starting it was only called neutrino as it was known yet that neutrino can have different flavours or be present in different generation ) and muon was discovered by Carl D Anderon in 1936 ( nearly after 40 years the discovery of the electrons ) and due to its mass it was in the beginning considered as a meson later it was observed that muon is more similar to electron than to meson.

Martin Lewis Perl with his colleagues SLAC LBL group discovery tau during a series of experiments between 1974 and 1977 ( while tau neutrino was discovered by the missing energy and momentum in the decay ).

And all the present data is consistent with all the three generations of leptons but particle physicists are still trying to find the fourth generation of the leptons.

Properties of Leptons

The spin statistics theorem tells us that leptons are fermions and thus Pauli’s exclusion law implies on them and thus no two leptons having the same species cannot have the same state at the same time.

Leptons closely related property chirality can be compared to a more easily visual properties known as helicity ( it is the direction of the spin of an particle related to its relative momentum).

The particles having the same spin with its momentum is known as right handed and otherwise they are called left handed and the Standard Model’s weak interaction treats left handed and right handed fermions differently and it is also states that the left handed fermions only participate in the weak interaction which is an example parity violation explicitly written in the records.

It is stated that right hand neutrino and left hand anti neutrino cannot have interaction with any particle.

It is also found that right handed fermions which are electrically charged and they don’t interact or engage in weak interaction specifically but they can  interact  electrically and thus are combined in the weak electro force although with different strengths.

Another of the important property of leptons is their electric charge and the electric charge determines the strength of their electromagnetic interaction and it also determines its electric field and how will it react to other electric and magnetic field and leptons possess intrinsic rotation in the form of their spin and the charged leptons generate magnetic field.

Thus each generation contains one electrically charged lepton and one non-electrically lepton with zero electric charge and the electromagnetic interaction of the charged leptons is expressed by the fact that the particles interact with the quantum of the electromagnetic field the photons. 

The size of the magnetic dipole moment is given by a formula( it is also referred to as anomalous magnetic dipole moments are very sensitive to the details of the quantum field theory model thus it gives or provides the opportunity for a precise model and structure.) and the given electron anomalous magnetic dipole moment theoretical and measured value is within the eight significant figures.

The members of each generation of the weak isospin doublets are assigned with the leptonic numbers which used under the standard model it is also known that neutrino oscillation violates the individual leptonic numbers and these violation are indicates that there is also a physics beyond the  Standard Model and thus it gives a more stronger conservation law the conservation of the total number of leptons and neutrino oscillation also obeys these law but this law is violated by a tiny amount of chiral anomaly.

Understanding any concept in physics involves decoding the definition of the terms associated. In the case of linear velocity, it thus becomes necessary to define linear and velocity individually. 

Linear velocity refers to the movement of an object along a straight line or a pre-defined axis. On the other hand, velocity implies the distance that a moving body travels in a specific direction within a particular time. Therefore, the combination of these two definitions will lead you to understand the basic concept of linear velocity. 

What is Velocity?

The term velocity can be used in various fields including physics, thermodynamics, chemistry et cetera before we go into understanding linear and angular velocity we will first define velocity as an individual term.

Velocity can be explained as a rate of change of the position of an object within a certain time limit or time range, it can be differentiated into two types, angular velocity, and linear velocity. To define velocity we will take an example so imagine driving down the road and looking down at the dashboard or any signboards as we move, the speedometer shows that the car is travelling at a speed of 65 mph, then we can say that the speed of 65 mph is the velocity, which is the rate of change of miles with respect to the hours that we see. The formula velocity equals distance divided by time can calculate an object’s linear velocity. In the formula, v denotes linear velocity, d denotes distance traveled, and t denotes time.

Now coming back to its different types, the linear velocity is simply the rate of change of the position of an object that is travelling along a straight path so any object that moves has a linear velocity, on the other hand, angular velocity only applies or can be applied to objects that move on a circular path and it can also be defined as the rate of change of the angular displacement over time. angular velocity, measured in rad/s, which can also be converted into degrees, is the change in angle over time. v=rω to calculate linear velocity from angular velocity.

V = ωr, where ω equals radians per second and r is the radius.

If the rotational period is t, then [w = frac{2pi}{t}]. As a result, [v = frac{2pi*r}{t}].

Linear velocity can be experienced in day-to-day life as we see so many moving objects that have a linear velocity like a person going for a walk, drive, running, or a bike ride, there can always be a linear velocity that can be observed. Furthermore, there are times when an object may be traveling along a straight path at a given constant speed, this can be said as the object traveling at a constant linear velocity, in simple words we can say that the object’s Lena velocity is not changing and hence constant. Linear velocity, measured in m/s, is the speed in a straight line.

When we talk about a circle the connection between an arc on a circle in the angle it subtends measured in radiance allows us to define quantities related to motion on a circle and through this also we can say that objects travelling along a circular path Exhibit 2 types of velocity when is linear and the other one is angular velocity as mentioned above. In addition to this, we can also understand uniform circular motion. Uniform circular motion can define the linear velocity that measures how the arc length changes over time. 

When we talk about circular motion we also talk about the direction of line velocity now the direction of the particle Salina velocity is tangential to the circular path that we see at any given point in that circular motion. Direction plays a very important role in defining the change in characteristics, velocity is a physical vector quantity which means that it requires both magnitude and direction to get its proper definition so if there is a change in speed, direction or both, the object philosophy changes and then we say that the object is an acceleration motion or accelerating.

What is Linear Velocity? 

In the most primary sense, linear velocity definition deals with the measurement of an object’s velocity when it moves along a specific direction. Therefore, it refers to the displacement of an object with respect to time. 

However, the object has to follow a specific straight line in terms of its movement. The SI unit of linear velocity is meter per second or m/s (m s-1). 

On the other hand, the linear velocity dimensional formula is M0L1T1

Also, you should know that it is a vector quantity, which indicates it has directional nature. 

What is the Formula for Linear Velocity? 

There are no points of difference between conventional velocity and linear velocity since both are vector quantities. 

Therefore, the linear velocity formula is – ν = d/t

For instance, suppose that a moving object covers a distance of 500 meters along a straight line within 10 seconds. In that case, the linear velocity of the object is – 

ν = 500 meters/10 seconds = 50 m/s or 50 m s-1. 

Logically speaking, linear velocity also applies to an object that moves in a circular direction, following a locus. In that case, it is termed angular velocity. 

What is Angular Velocity? 

Angular velocity is primarily the ratio of the angle that an object covers within a particular amount of time. In this instance, ϴ refers to the angular displacement at which a body rotates around a fixed axis. 

The formula expressing angular velocity is, therefore – νr = r.ω, 

Where νr refers to the angular velocity, ω implies time/radians, and r stands for the radius of the travelled path. Moreover, 2π radians equal 3600 in this case. You should also know that every point of the object’s trajectory has the same angular velocity because it remains constant throughout its journey. 

Can you Solve these Linear Velocity Problems?

• Amrita runs in a single direction for 10 minutes at a constant velocity. She successfully covers 1.2 km from when she started running. What will be her linear velocity in SI units? 

• The linear velocity of a specific car along a straight highway is 150 km/h, and it travels 50 km within a specific time. How much time (in seconds and minutes) will it take the car to cover that distance? 

• A moving object X has a linear velocity of 100 m/s and travels from point A to B in 1 minute 40 seconds. What is the distance between points A and B? 

How does Linear Velocity Differ from Speed? 

Even though both velocity and speed aim to find out the distance that a moving object covers within a certain period, there are some points of difference between them.

First of all, speed is a scalar quantity. This suggests that the expression of speed in m/s or m s-1 conveys only the magnitude. It does not imply anything about the
direction in which the moving object travels. Certain instances of scalar quantities are energy, mass, and time. 

On the other hand, linear velocity specifies the direction of travel. It is because velocity is a vector quantity and suggests both the magnitude and direction of the moving body. Some other examples of vector quantities are force and momentum. 

Now that you know what is linear velocity, make sure that you go through related topics to gather comprehensive knowledge on the same. Also, you can download our app to benefit from our interactive learning experience from professionals in the field of physics. 

Many a time students get scared merely by hearing the name of the topic of thermodynamics itself as if it is some scary mammoth. Are you one of them? Do not worry, is here to help you.

Thermodynamics is nothing but the study of the relations between heat, work, temperature, and energy. It is a very practical subject whose examples can be observed in daily life itself like when you boil water to make tea or when you pour that tea into a thermos. 

The Foundation of Thermodynamics is laid over its four laws which are 

• Zeroth law

• First law

• Second law

• Third law 

   

Zeroth of Thermodynamics

It states that if two systems are in thermodynamic equilibrium with a third system, then the two original systems are also in thermal equilibrium with each other. If A is in thermodynamic equilibrium with C and B is also in thermodynamic equilibrium with C, then A and B are also in thermodynamic equilibrium.

The First Law of thermodynamics

The first law of thermodynamics is nothing but the law of conservation of energy. It states that energy can neither be created nor it can be destroyed. It can only be converted from one form to another.

The Second Law of Thermodynamics

The second law of thermodynamics states that any isolated system’s entropy always increases. Isolated systems evolve spontaneously towards thermal equilibrium— the system’s state of maximum entropy. In simple terms, Universe entropy (the ultimate isolated system) only increases and never decreases.

A straightforward way of thinking about the second law of thermodynamics is that if it is not cleaned and tidy, a room will eventually get messier and messier over time –no matter how careful one is to keep it clean.

The Third Law of Thermodynamics

The third thermodynamic law states that the entropy of a system approaches a constant value as it reaches absolute zero. The entropy of a system at absolute zero usually is zero and is determined in every case only by the number of different ground states it has. Entropy for a pure crystalline material at absolute zero temperature (ideal order) is 0. This statement holds if only one minimum energy condition exists for the perfect crystal.

MCQs of 2nd and 3rd Law of Thermodynamics

1. A refrigerator has a performance coefficient of 5. Calculate the ambient heat discharged if the temperature inside the freezer is -20oC

1. 11oC

2. 41oC

3. 21oC

4. 31oC

Ans: D

2. Which of the following factors affects the heat of reaction based on with Kirchhoff Equation

1. Molecularity

2. Temperature

3. Pressure

4. Volume

Ans: B

3. Chemical Dissociation of all reactions is

1. Exothermic

2. Reversible

3. Endothermic

4. Reversible and Endothermic

Ans: D

4. Select the largest unit of Energy

1. Electron volt

2. Joule

3. Calorie

4. Erg

Ans: C

5. What is the unique characteristic feature of a perfect Black Body

1. A good absorber only

2. A good radiator

3. A good absorber and a good radiator

4. Neither a radiator nor an absorber

Ans: C

6. Which Thermodynamic process where heat is not exchanged with the surroundings is

1. Isothermal

2. Adiabatic

3. Isobaric

4. Isotropic

Ans: B

Entropy

In physics and chemistry, entropy is an important concept, and it can be extended to other sciences, including cosmology and economy. It’s part of thermodynamics in physics. It is a core concept in physical chemistry.

Solved MCQs on Entropy

This series of Multiple-Choice Questions & Answers (MCQs) in Thermodynamics primarily focuses on “Entropy Theory and its Applications.”

1. Which of the following is correct?

1. For an isolated system, dS>=0

2. For a reversible process, dS=0

3. For an irreversible process, dS>0

4. All of the mentioned

Ans: D

Explanation: For an isolated system with no exchange of energy with environment Q=0 and also dS>=dQ / T.

2. According to the entropy theorem, the entropy of an isolated system can never decrease and will remain constant only when the process is reversible.

1. True

2. False

Ans: B

Explanation: This is the declaration for the principle of increase of entropy.

3. Entropy may decline locally somewhere within the isolated system. How can one clarify this statement?

1. This cannot be possible

2. This is possible because it can decrease the entropy of an isolated system.

3. This must be balanced by increased entropy somewhere within the system.

4. None of the mentioned

Ans: C

Explanation: The net effect of an irreversible process is an increase in entropy of the entire system.

4. Clausius summed up the first and second laws concerning thermodynamics as

1. The energy of the world is constant

2. The entropy tends towards a maximum

3. Both of the mentioned

4. None of the mentioned

Ans: C

Explanation: Clausius gave these two statements.

5. The entropy of an isolated system continuously ____ and becomes a ____ at the state of equilibrium.

1. decreases, minimum

2. increases, maximum

3. increases, minimum

4. decreases, maximum

Ans:  B

Explanation: If an isolated system’s entropy differs from some parameter, then that parameter has a certain value that maximizes the entropy.

6. The entropy principle is the quantitative statement of the second law of thermodynamics.

1. True

2. False

Ans: a

Explanation: This is an overall fact about the entropy principle.

7. Which of the following may be regarded as applying the principle of entropy?

1. Transfer of heat through a finite temperature difference

2. Mixing of two fluids

3. Maximum temperature attainable from two finite bodies

4. All of the mentioned

Ans: D

Explanation: These are some general applications of the entropy principle.

8. The final temperatures of two bodies, initially at T1 and T2 can range from

1. (T1-T2)/2 to √(T1*T2)  

2. (T1+T2)/2 to √(T1*T2)  

3. (T1+T2)/2 to (T1*T2)

4. (T1-T2)/2 to (T1*T2)

Ans: B

Explanation: (T1+T2)/2 is when no work is done, and sqrt(T1*T2) is the temperature with maximum work distribution.

9. Which of the following processes exhibit external mechanical Irreversibility?

1. Isothermal dissipation of work

2. Adiabatic dissipation of work

3. Both of the mentioned

4. None of the mentioned

Ans: C

Explanation: These processes reveal external mechanical irreversibility.

10. Which of the following laws was expressed by Nernst?

1. The first law of thermodynamics

2. The second law of thermodynamics

3. Third law of thermodynamics

4. None of the above

Ans: C

Explanation: Third law of thermodynamics was expressed by Nernst and it states that entropy of a system at absolute zero remains constant.

Importance of MCQs

• MCQs play a very important role in gauging a student’s understanding of a specific topic. 

• It helps in evaluating one’s objective understanding of a topic.

• All the entrance exams conducted after Class 12 for getting admission into various professional degree courses consist of MCQ type of questions only

• These questions are a very good way for you to test your level of preparation

• These MCQs can act as your mock test for various exams

•  All of these are available for free on ’s website

• You can access them anytime from anywhere.

Magnetic moment, which is also known as magnetic dipole moment, is the quantitative measure of the tendency of an object to align with a magnetic field. In other words, the magnetic moment can be described as the magnetic strength and orientation of a magnet or other object that produces a magnetic field. 

The magnetic moment can be generated using two methods which are the motion of the electric charge method and the spin angular momentum method. The magnetic moment of an object is typically measured by an instrument known as the magnetometer.

 

The magnetic moment is a vector quantity that has dimension [IL2]. The SI unit of magnetic dipole moment is Am2, while the CGS unit is emucm2. The relationship between these two quantities can be defined as 1 emucm2 = 10-3 Am2

Pole Strength of a Magnet

The pole strength of any magnet can be defined as the Force with which material gets attracted towards the magnet. Pole strength is a vector quantity. The magnetic moment of an object is the product of pole strength and the length of the magnet. 

Since pole strength and magnetic moment are directly related, the force on the north pole of the magnet points towards a magnetic field B and the force on the south pole of the magnet is opposite to that. Both the forces have a magnitude F. 

The moment of a couple (i.e. torque) is given by,

N = F × r

The direction of the torque is perpendicular to the plane of the paper and its magnitude is given by,

N = F r sinθ 

Considering the magnetic moment of the bar magnet to be m, the torque has a magnitude,

N = mBsinθ

Comparing the expressions,

F r sinθ  = mBsinθ

The quantity

F= [frac{mB}{r}]

is equivalent to electric charge and it is referred to as the “pole strength”. The strength of north pole is taken to be +qm and that of south pole is chosen as -qm.

qm=[frac{m}{r}]

According to the pole strength formula, the pole strength of a magnet is given by the ratio of magnetic moment to its effective length (called the magnetic length). SI unit of pole strength is A . m.

Force and Potential Energy

The force on a magnetic moment m due to a magnetic field B is given by,

F = (m . ▽)B

The potential energy is as follows,

U = -m . B

Magnetic Moment in Chemistry

An electron revolving around the nucleus of an atom, constitutes a closed current-carrying loop. The magnetic moment of an electron is,

m = [-frac{mu g}{h}L]

Here, L is the angular momentum and it is quantized in units of Planck’s constant ħ.

is called Bohr magneton defined as,

μB = [frac{ehbar}{2m_e}]

Here, the mass of an electron, me = 9.1×10−31kg 

Charge of an electron, e = 1.6×10−19C 

Planck’s constant, h= 2πℏ = 6.626×10−34J.s.

The magnetic moment due to the orbital motion of an electron (with orbital quantum number l) as a magnitude is given by,

ml = [sqrt{l(l+1){mu _B}}]

Apart from this, an electron has a magnetic moment due to its intrinsic spin (s=1/2). It has a magnitude given by the spin magnetic moment formula,

Ms = [2sqrt{s(s+1){mu _B}}]

Protons and neutrons are spin half (s = 1/2) particles. The magnetic moments have magnitudes.

Mp = [g_psqrt{s(s+1)}frac{ehbar}{2M_p}]

Mn = [g_nsqrt{s(s+1)}frac{ehbar}{2M_n}]

Here, Mp and Mn are the masses of protons and neutrons respectively, and gp and gn are empirical constants. 

Did You Know?

• Materials, consisting of atoms with unpaired electrons are called paramagnetic. Each atom behaves as a tiny dipole moment. Normally, they remain randomly oriented. But in the presence of an external magnetic field, the dipoles tend to get arranged parallel to the magnetic field.

• Total magnetic moment of an electron is a sum of orbital and spin magnetic moments. 

• Magnetic moment of an electron is opposite to its angular momentum. Like angular momentum and spin, magnetic moment is also quantized.

• Ferromagnetic atoms have a much higher value of magnetic moment than that of paramagnetic atoms.

• Most of the paramagnetic materials are colored.

• Early theories concerning magnetostatics considered the existence of magnetic monopoles. But Gauss’ law discards the concept of monopoles.

• Magnetic field strength at a point, due to a magnetic moment, is inversely proportional to the cube of the distance of that point from the dipole.

Mass is the fundamental attribute of any physical body.

All the objects have a matter inside them and the measurement of the matter is the mass. The total mass of the system is assumed to be constant. This means that the mass remains unaffected by the gravitational field strength, regardless of the location, the object or person is in.

The mass has a magnitude that is usually measured in kilograms and grams. Therefore, it is a scalar quantity.

We are on earth and we measure things on earth with earth’s gravity.

If your weight is 70 kg which means you weigh 70 kg and the scale would read it 70kg or 154 lbs.

Mass Definition

Mass is defined as the measure of the matter inside a body.

In physics, mass is a quantitative measurement of inertia.

Let’s understand the concept of mass by understanding Newton’s second law.

For example, a body of mass, ‘m’ is moving with an acceleration ‘a.’ The force, ‘F’ is applied to the body given by,

F = m . a

Here, mass is a measure of its resistance to acceleration when a force is applied to the body.

Therefore, the greater the mass of a body, the minimum change produced by an applied force.

Mass Meaning

Mass is referred to as the amount of matter contained in a body.

For example, a human body has bones, muscles, tissues, RBC, WBC. As combined, they form a body’s mass.

A person or object may be weightless on the moon because of lack of gravity while he maintains the same mass at all places without considering his location.

Weight Definition

The weight is the amount that something weighs. 

It is defined as the force that acts at all times on the objects near the earth’s surface.

In the field of science and engineering, the weight of an object is related to the force acting on that object, either due to gravity or due to a reaction force that holds it in a place. 

In simple terms, it is the force with which a body is pulled towards the earth.

Therefore, weight is the measure of the heaviness of an object.

Relationship between Mass and Weight

Weight is defined as the force of gravity with which a body is attracted to Earth or another celestial body, and is equal to the product of the object’s mass, and the acceleration of gravity given by,

W =  F = mg

The above equation is applicable at all times even when the object is not accelerating. This means the object is under free-fall and no external force other than gravity is acting upon it. 

Here, W is the weight of the body

F = external force

m  = mass of the body

g  = acceleration due to gravity

Here, g is the measure of the intensity of the gravity field in N/kg at any location.

For example, if I weigh 24 kg on earth,  then my mass on the moon will be 1/ 6 to the weight on the earth i.e., 4 kg on the moon.

The mass on the Moon is less than the Earth. However, its gravity is less than the Earth.

Unit of Mass and Weight

In physics, each object has a unit that determines the standard measurement of that body. 

Therefore, a physical quantity such as mass also has a unit. In International systems, SI, the mass is measured in Kilograms denoted by the symbol kg.

Here, weight is a vector quantity measured in Newton, symbolized by N.

Mass vs Weight

Do You know?

Some interesting facts about mass and weight are:

• The mass does not remain constant.

• Nuclear reaction: In this reaction, a tiny amount of matter is converted into a large amount of energy, this reduces the mass of the substance.

Chapter 10 class 11 in physics is the mechanical properties of fluids. Students get to score higher scores in subjects like physics because the questions in competitive exams from the subject are based on basic concepts, formulas and problems related to the chapter. Theories are difficult to memorize and hence, there arises a chance of losing marks. In this chapter, our experts have tried to explain these concepts in detail so that students find it easy to understand and practice problems on the basis of understanding of the chapter.

In this chapter, students may learn in detail the mechanical properties of liquids and gases, pressure, streamline flow, viscosity, surface tension and so on.

Introduction

As we all know, a fluid is anything that has no fixed shape. Both liquids and gases are referred to as fluids because they have the tendency to flow. Fluids can yield to slightest external pressures. The study of mechanical properties of fluids is called Hydrostatics. The volume of liquid or gas depends on the pressure acting on it. Since liquids have a fixed volume, the change in volume due to the change in external pressure is less. It is not the same in the case of gases, as they do not have a fixed volume.

Let’s study more about the concepts of mechanical properties of fluids

Notes of Mechanical Properties of Fluids

Fluids are liquids and gases with the property to flow in a certain direction on the application of external force. Two major topics are studied when we talk about the mechanical properties of fluids. They are- hydrodynamics and hydrostatics.

Hydrodynamics

In physics, hydrodynamics is the study that concerns the forces acting on or exerted by fluids. It deals with the motion of fluids and the forces acting on solid bodies that are immersed in fluids. It also focuses on the motion relative to them. In short, it is the study of fluids in motion. Thus, it is a vast branch of science, which we will study more later.

In this chapter, we will focus more on Hydrostatics

Hydrostatics

This branch of physics is concerned with the fluids at rest.

Pascal’s Law

Pascal made an observation that the pressure in a fluid that is at rest is the same at all points, provided they are at the same height. He also inferred that the pressure difference depends upon the vertical distance between the two points. Thus, the pressure difference applied to the fluid which is enclosed can be transmitted undiminished to every point of the fluid and the container vessel’s walls as well.

It can thus be noted that when an incompressible fluid is passing between every second in a pipe of non-uniform cross-section, the volume will be the same as the steady flow.

Bernoulli’s Principle and Equation

Bernoulli’s principle states that the total energy of the water always remains constant, therefore when the flow of water in a system increases, the pressure necessarily decreases. When water starts to flow in a hydraulic system the pressure drops and when the flow of water stops, the pressure rises again.

Therefore, in a hydraulic system, the total energy head is equal to the sum of three individual energy heads.

This can be expressed as follows-

Total Head = [Elevation Head + Pressure Head + Velocity Head]

Where,

• Elevation head- is the pressure due to the elevation of the water

• Pressure head- is the height of a column of water that a given hydrostatic pressure in a system could support

• Velocity head- is the energy present due to the velocity of the water.

Surface Tension 

The amount of energy required to increase the surface of the liquid by unit area is defined as surface tension. It means it is the property of the surface of the liquid to resist force. Moreover, it is the force that holds the liquid molecules bound together. Therefore, surface tension is the amount of the extra energy which the molecules at the interface have when compared to the interior. Surface tension is denoted by the Greek letter ‘sigma’.

Viscosity

Viscosity is the measure of the resistance exerted by fluids to gradual deformation by shear or tensile stress. Thus, it can be considered as the fluid’s resistance to flow. When we say honey is thicker, milk is thinner, we intend to mean the viscosity of the liquid. Thus, the liquid that tends to flow less is more viscous.

It is measured in terms of a ratio of shearing stress to the velocity gradient in a fluid.

The equation to determine the viscosity of a fluid

When a sphere of radius a is dropped in a fluid of viscosity v, the viscosity is given by η=2ga2(Δρ)9v

Where,

• ∆ρ is the density difference between the fluid and the sphere

• a is the radius of the sphere

• g is the acceleration due to gravity

• v is the velocity of the sphere