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(PHYSICS)
Chapter 1 HEAT
HEAT HEAT IS THE FORM OF ENERGY WHICH MOVES
FROM ONE BODY TO ANOTHER BODY BECAUSE
OF TEMPERATURE DIFFERENCE.
ITS UNIT IS JOULE (J) AND OLD UNIT IS
CALORIE
1 CALORIE = 9.18 CALORIES
1J = 10000000 ERGS
TEMPERATURE THE DEGREE OF HOTNESS OR COLDNESS IN A
BODY IS KNOWN AS TEMPERATURE.
SI UNIT OF TEMPERATURE IS KELVIN (K)
IT CAN BE MEASURED IN CELCIUS DEGREE AND
FARHENITE
F = 9 * (C) + 32 DEGREE
K = (C) + 273.15
BOILING POINT = 100 DEGREE CELCIUS
FREEZING POINT = 0 DEGREE CELCIUS
FULL FORMS
Q = HEAT SUPPLY
M= MASS OF THE OBJECTS
S=SPECIFIC HEAT
DELTA T = CHANGE IN TEMPERATURE
( FINAL TEMPERATURE - INITIAL
TEMPERATURE)
L
= LATENT HEAT
SPECIFIC HEAT IT IS THE HEAT REQUIRED TO INCREASE THE
TEMPERATURE OG 1 kg BY 1calorie
ITS SI UNIT IS J\KG\K
Q=msDELTA T
LATENT HEAT
IT IS THE HEAT REQUIRED IKG OF SUBSTANCE
FROM ITS SOLID STATE TO LQUID STATE OR
LIQUID STATE TO GASEOUS STATE .
ITS UNIT IS J\KG
Q=mL
FORMS OF HEAT
1) CONDUCTION IT IS THE FLOW OF HEAT THROUGH A MATTER
FROM A PLACE OF HIGH TEMPERATURE TO LOW
TEMPERATURE.
NO MOVEMENT OF MATTER AT A WHOLE.
2) CONVECTION HEAT FLOWS FROM HOTTER PART TO COLDER
PART.
ACTUAL MOVEMENT OF MATTER OCCURS
HERE.
3) RADIATIONHEAT FLOWS FROM HOT BODY TO COLD BODY
NO MEDIUM IS REQUIRED.
CHAPTER 2
Time and motion
TIME - THE GAP BETWEEN TWO EVENTS IS
CALLED TIME .
MOTION- IF THE POSITION OF THE BODY
CHANGES WITH RESPECT TO TIME IS CALLED
AS MOTION.
REST - IF THE POSITION OF BODY DOESNT
MOVE WITH RESPECT TO TIME IS SAID TO BE
THAT BODY IS AT REST STATE.
REST AND MOTION ARE RELATIVE TERMS
DENSITY = MASS\VOLUME
D = M\V
SCALAR QUANTITY
THESE HAVE ONLY MAGNETUDE .
VECTOR QUANTITY
THESE HAVE MAGNETUDE AND DIRECTION
BOTH.
DISTANCE IT IS THE LENGTH OF ACTUALL PART TAKEN .
IT DEPENDS ON PART OF JOURNEY .
ITS SCALAR QUANTITY .
DISPLACEMENTIT IS LENGTH OF SHORTEST PART TAKEN .
IT DOESNT DEPENDS ON PART OF JOURNEY.
ITS A VECTOR QUANTITY .
SPEED SPEED = DISTANCE / TIME TAKEN
AVERAGE SPEED AVG. SPEED = TOTAL DISTANCE / TOTAL TIME
FULL FORMS
v = FINAL VELOCITY
u = INITIAL VELOCITY
a = ACCELERATION
t = TIME
s = DISPLACEMENT
ACCELERATION (a)
RATE OF CHANGE OF VELOCITY WITH RESPECT
TO TIME IS KNOWN AS ACCELERATION .
IT IS A VECTOR QUANTITY
ITS SI UNIT IS m/sec sq.
EQUATIONS ON MOTION
a = v - u/t
v-u = at
v = u +at
s = ut + 1/2 at square
v =s/t
a = v/t
SIMPLE PENDULUM
AMPLITUDE
IT IS THE MAXIMUM DISPLACEMENT FROM
MEAN POSITION
TIME PERIOD
IT WILL NOT CHANGE WITH ITS LENGTH , MASS
AND DENSITY
T = 2 PIE * SQ. ROOT OF L/G
Chapter 3
LIGHT
LIGHT LIGHT IS A INVISIBLE ENERGY WHICH CAUSES
SENSATION OF VISION IN US .
IT TRAVELS IN STRAIGHT LINE .
RAY THE DIRECTION OF THE PATH IN WHICH LIGHT
IS TRAVELLING IS CALLED RAY .
BEAM A BEAM IS A STREAM OF LIGHT AND IS SHOWN
BY NUMBER OF RAYS .
TYPES OF BEAMS
THERE ARE MAINLY THREE TYPES OF BEAMS 1) PARALLEL BEAM - WHEN THE RAYS OF LIGHT
TRAVEL PARALLEL TO EACH OTHER , THEN THE
COLLECTION OF SUCH RAYS IS CALLED
PARALLEL BEAM .
2)DIVERGENT BEAM - WHEN THE RAYS OF
LIGHT START FROM A POINT AND TRAVEL IN
VARIOUS DIRECTION ,THEN THE COLLECTION
OF SUCH RAYS ARE CALLED DIVERGENT BEAM .
3)CONVERGENT BEAM - WHEN THE RAYS OF
LIGHT COMING FROM DIFFERENT DIRECTION
MEET AT A POINT ,THEN THE COLLECTION OF
SUCH RAYS IS CALLED CONVERGENT BEAM .
LIGHT IS AN INVENSIBLE ENERGY PRODUCED
BY BULB. ITS SPEED IS 3 * 1000000000 m/s
REFLECTION OF LIGHT
THE MIRROR CHANGES THE DIRECTION OF
LIGHT . THE CHANGE OF DIRECTION BY A
MIRROR IS CALLED REFLECTION OF LIGHT .
IMAGE
THE OBJECT WHICH APPEARS BEHIND THE
MIRROR IS CALLED AS IMAGE. THERE ARE TWO
TYPES OF IMAGES
1 REAL IMAGE
2 VIRTUAL IMAGE
REAL IMAGE
AN IMAGE WHICH CAN BE OBTAINED ON
SCREEN IS CALLED AS REAL IMAGE.
REAL IMAGES ARE ALWAYS ERECT .
VIRTUAL IMAGES
AN IMAGE WHICH CANNAOT BE OBTAINED ON
SCREEN IS CALLED VIRTUAL IMAGE .
MIRROR
ANY POLISHED OR SHINING SURFACE ACT AS
A MIRROR . THERE ARE THREE TYPES OF
MIRROR
1.PLANE MIRROR
2.CONCAVE MIRROR
3.CONVEX MIRROR
PLANE MIRROR
A PLANE MIRROR FORMS REAL IMAGE AND IS
ERECT .
IT IS OF THE SAME SIZE AND IT IS SAME
DISTANCE FROM MIRROR AS THE OBJECT IS IN
FRONT OF IT .
WE CAN ALSO SEE RIGHT SIDE TO LEFT SIDE
AND LEFT SIDE TO RIGHT SIDE THIS IS
LATERAL INVERSION .
CONCAVE MIRROR
A CONCAVE MIRROR CAN FORM REAL AND
INVERTED IMAGE .
WHEN THE OBJECT IS PLACED VERY CLOSED
TO MIRROR THE IMAGE FORMED IS VIRTUAL ,
ERECT AND MAGNEFIED .
USES OF CONCAVE MIRROR
CONCAVE MIRRORS ARE USED FOR MANY
PURPOSES DOCTORS USE CONCAVE MIRRORS
FOR EXAMINING EYES, EARS , NOSE AND
THROAT .
CONCAVE MIRRORS ARE USED BY DENTISTS
TO SEE AN ENLARGED IMAGE OF TEETH.
THE REFLECTORS OF TORCHES, HEADLIGHTS
OF CARS AND SCOTERS ARE CONCAVE IN
SHAPE.
CONVEX MIRROR
IMAGE FORMED BY A CONVEX MIRROR IS
ERECT, VIRTUAL AND SMALLER IN SIZE THAN
THE OBJECT .
Lenses
The magnifying glass is actually a type of
lense.
LENSES ARE WIDELY USED IN SPECTACLES
TELESCOPES AND MICROSCOPES .
TYPES OF LENSES
THERE ARE TWO TYPES OF LENSES
1.CONCAVE LENSE
2.CONVEX LENSE
CONCAVE LENS
THE LENSES WHICH FEEL THINNER IN THE
MIDDLE THAN AT THE EDGES ARE CONCAVE
LENSES .
A CONCAVE LENS ALWAYS FORMS ERECT,
VIRTUAL AND SMALLER IMAGE THAN THE
OBJECT .
composition OF WHITE LIGHT
WHITE LIGHT IS COMPOSED OF SEVEN
COLOURS THEY ARE VIOLET , INDIGO , BLUE ,
GREEN , YELLOW , ORANGE , RED.
CHAPTER 4
Electric current and its effect
Unit of charge is Coulomb (C)
Charge of 1 electron = -1.6 * 10-19 C
Charge of 1 proton = 1.6 * 10-19 C
Electric Current (I)
I = AMOUNT OF CHARGE FLOWN / TIME TAKEN
I = q/t
SI unit of electric current is AMPERE .(A)
Convection of current is always taken opposite direction
of the flow of electrons .In a circuit electron flows from
negative terminal to positive terminal . Current flows
from positive to negative terminal .
RESISTANCE
It is the device which will decrease the amount of
current in circuit . Its SI unit is OHM Ω .
Types of circuits
1) Series circuit- In series circuit current is same through
the wire .{figure 1(a) }
2) Parallel circuit - In parallel circuit voltage is same
across all the circuit branches .{figure 1(b)}
OHM S LAW
At a constant temperature current flowing in a
resistance is proportional to voltage applied in a
resistance .
I = V/R
V =IR
In our household supply normally 220 volts and all
electric appliance are connected in parallel .
Heating effects of electricity
Heat is produced by resistance(R) in time (T) is given as
H = I2RT
H = V2/R *T
H = VIT
POWER
Power is work / time taken
SI unit of power is watt .
1W = 1J/S
1KW =1000W
1MW =1000000W
1HP = 746 W
P =VI
P =V2/R
I = P/V
KILLOWATTHOUR ( KWH)
IT IS THE ENERGY CONSUMED BY ONE INSTRUMENT OF
POWER 1KW IF USED FOR 1 HOUR .
1KWH = 3.6*1000000 J
Rnets IN PARALEL AND SERIES CIRCUIT
PARRALEL CIRCUIT
1/Rnet = 1/R1 + 1/R2 -----------SERIES CIRCUIT
Rnet = R1 + R2 ---------------
CHAPTER 5 – GRAVITATION
Gravitation is the attraction between objects because of
their mass. Objects can range in size from sub-atomic
particles to celestial masses, such as planets, stars and
galaxies. Other properties of gravitation include attraction
to the center or mass, escape velocity and gravity.
The concept of that matter attracts other objects was
formulated by Isaac Newton as the Law of Universal
Gravitation. This theory has been superseded by newer
theories of gravitation, such as Albert Einstein’s Theory of
General Relativity and the Theory of Quantum Gravitation.
The Universal Gravitation Equation defines the force of
attraction between two objects in ordinary situations. The
equation can be simplified to give the gravity equation for
objects near Earth.
Properties of gravitation all objects consisting of matter
exhibit the property of gravitational attraction and tend
to move toward each other. This property is considered
universal and exists throughout the Universe.
No shield As far as we know, there is no way to shield the
effect of gravitation. There are theories that there exists
"dark matter" that repels standard matter, however dark
matter has never been detected.
Center of mass between two objects, there is a center of
mass of the objects. When the objects move toward each
other, the will meet at the center of mass. If one is
revolving around the other, as in the case of a moon
around a planet, both objects are actually rotating around
the center of mass.
Escape velocity It is possible for an object to be propelled
at a sufficient velocity away from another object that it
will overcome the gravitational attraction between the
two. An example of this is when a rocket escapes the
gravitation from the Earth.
Gravity The expressions gravity and gravitation are often
commonly interchanged. However, the correct scientific
terminology considers gravity as a special case of
gravitation for objects near the Earth.
For gravitation close to other large objects, you should
include the name of the object, such as: "gravity of the
Moon" or "gravity of the Sun."
For astronomical situations, gravitation is the correct term
to use.
Gravitational theories There have been several theories
trying to explain the cause of gravitation.
Law of Universal Gravitation In 1687, Isaac Newton
formulated the Law of Universal Gravitation, which states
that all objects are attracted toward other objects, due to
a force acting at a distance, called gravitation.
Theory of General Relativity In 1915, Albert Einstein gave
another interpretation of gravitation in his Theory of
General Relativity. He stated that gravitation was the
result of the curvature of space toward matter and not
due to some force.
Verification of the theory was in explaining the unusual
orbit of the planet Mercury and measuring the effect of
gravitation on deflecting light waves as they pass a star.
Theories of Quantum Gravitation Recent considerations in
Quantum Physics say that gravitation is one of four
fundamental forces in nature. The force of each is created
by an exchange of special or virtual particles. In the case
of gravitation, the particle is called the graviton. This
interaction leads to an explanation of gravitation at very
small distances.
Gravitation Equation Just as there are several theories
about the cause of gravitation, likewise, there are several
equations that define the force.
Universal Gravitation Equation Newton formulated the
Universal Gravitation Equation, which allows the
calculation of the force between two objects. The
equation is:
F = GMm/R2
where




F is the force of attraction between two objects in
newtons (N)
G is the universal gravitational constant in N-m2/kg2
M and m are the masses of the two objects in
kilograms (kg)
R is the distance in meters (m) between the objects,
as measured from their centers of mass
Gravity equation The gravity equation is a simplification of
the gravitational equation for objects relatively close to
the Earth:
F = mg
where


F is the force pulling objects toward the Earth in
newtons (N) or pound-force (lbs)
m is the mass of the object in kg or pound-mass

g is the acceleration due to gravity in meters per
second squared (m/s2) or feet per second squared
(ft/s2)
CHAPTER 6
WINDS,STORMS AND CYCLONES
Air around us exerts pressure.
Air expands on heating and contracts on cooling.
Warm air rises up, whereas comparatively cooler air
tends to sink towards
the earth’s surface.
As warm air rises, air pressure at that place is reduced
and the cooler
air moves to that place.
The moving air is called wind.
Uneven heating on the earth is the main cause of wind
movements.
Winds carrying water vapour bring rain.
High-speed winds and air pressure difference can cause
cyclones.
It has become easier to monitor cyclones with the help of
advance
technology like satellites and radars.
Self-help is the best help. Therefore it is better to plan in
advance and
be ready with defenses against any approaching cyclone.
The following flow chart will help you to understand the
phenomena
that lead to the formation of clouds and falling of rain and
creation of
storms and cyclones: