The study of magnetic effects of electric current is an essential part of physics, providing insights into the relationship between electricity and magnetism. In Class 10, students delve into this fascinating realm, understanding the principles behind electromagnetism, magnetic field lines, and applications of electromagnetic induction. Let's explore this topic in detail.
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Magnetic Effects of Electric Current for Grade 10th StudentsMurari Parashar
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In this chapter, we will study the effects of electric current : Moving charges or electric current generates a magnetic field. This is useful to CBSE Students.
Magnetic Effects of Electric Current for Grade 10th StudentsMurari Parashar
Â
In this chapter, we will study the effects of electric current : Moving charges or electric current generates a magnetic field. This is useful to CBSE Students.
Very important Chapter of physics because it contains all the important laws needed to understand concepts in physics.
And i hope it will be helpful to you
a) Magnetic field :-
The region around a magnet where the force of attraction or repulsion can be detected is called magnetic field.
Magnetic field around a magnet can be detected by using a magnetic compass.
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Very important Chapter of physics because it contains all the important laws needed to understand concepts in physics.
And i hope it will be helpful to you
a) Magnetic field :-
The region around a magnet where the force of attraction or repulsion can be detected is called magnetic field.
Magnetic field around a magnet can be detected by using a magnetic compass.
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For more information, visit-www.vavaclasses.com
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For more information, visit-www.vavaclasses.com
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Magnetic Effects of Electric Current Class 10 Free Study Material PDF
1. MAGNETIC EFFECT OF CURRENT
1. Introduction: Magnetic properties
2. Magnetic Effect of Current â Oerstedâs Experiment
3. Ampereâs Swimming Rule
4. Maxwellâs Cork Screw Rule
5. Right Hand Thumb Rule
6. Magnetic Field due to Infinitely Long Straight Current â carrying Conductor
7. Magnetic Field due to a Circular Loop carrying current
8. Magnetic Field due to a Solenoid
9. Flemingâs left hand rule
10.Electric motor(AC/DC)
11.Electromagnetic Induction and Flemingâs right hand rule
12.Electric generator (AC/ DC): Dynamo
13. Domestic electric circuit
Topics covered
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2. MAGNETIC FIELD AND FIELD LINES
Properties of Magnets:
1. They have two permanent poles namely, North and South and poles cannot be isolated.
2. Like poles repel each other and unlike poles attract each other.
3. When magnet is cut into pieces they will behave like separate magnets with same
property but lesser magnetic strength compared to whole magnet.
4. The freely suspended bar magnet will align in geographic N â S direction.
5. When magnet is subjected to mechanical damages (falling on a hard surface, heating,
piling, hammering etc.) they lose their magnetic properties
6. Depending on application we have, i) dumbbell magnet, ii) ring magnet, iii) bar
magnet, iv) horse shoe magnet, v) compass needle etc.
7. Note: There is a magnet without poles is called toroid, whose north and south poles are
joined.
8. Magnets are naturally available (Earth) and can be prepared artificially for use.
Introduction:
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3. MAGNETIC FIELD AND FIELD LINES
Definition: Magnetic field is space or region surrounding the magnet (or current carrying
conductor) in which another magnet will experience the force of magnetostatics. It is
denoted by B SI unit T (tesla) and a vector.
Definition: Magnetic field lines are the imaginary path in which an isolated north pole can
travel from one pole to another in space.
Properties:
1. Magnetic field lines or Magnetic lines of force, travel from north pole and reach south
pole in its vicinity or travel up to infinity.
2. M.F.L. are continuous closed curves and can pass through conductors
3. Note: Superconductors does not allow MFL to enter inside hence B = 0 (inside).
4. The tangent drawn at any point on the MFL gives direction of MF at that point.
5. No two MFL can intersect each other since two value of MF doesnât exist at a point.
6. MFL are crowded at strong MF (poles) but diverged at weak MF region.
Introduction:
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4. MAGNETIC FIELD AND FIELD LINES OF A BAR MAGNET
Experimental image Illustrative diagram
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5. N
Magnetic Effect of electric Current:
An electric current (i.e. flow of electric charge) produces magnetic effect in
the space around the conductor called strength of Magnetic field or simply
Magnetic field.
Hans Christian Oerstedâs Experiment:
When current is passing through the wire over
the compass needle in anti-clockwise direction,
the needle was found to deflect towards West
direction from its normal position.
E
K
I
N
E
K
I
When current direction is reversed through the wire
over the compass needle, the needle was found to
deflect towards East direction from its normal
direction.
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6. B
B
Rules to determine the direction of magnetic field:
Ampereâs Swimming Rule or
SNOW Rule:
Imagining a man who swims in the
direction of current from south to north
facing a magnetic needle kept under
him such that current enters his feet
then the North pole of the needle will
deflect towards his left hand, i.e.
towards West.
Maxwellâs Cork Screw Rule or Right
Hand Screw Rule:
If the forward motion of an imaginary
right handed screw is in the direction of
the current through a linear conductor,
then the direction of rotation of the
screw gives the direction of the
magnetic lines of force around the
conductor.
S
I
I I
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7. Right Hand Thumb Rule or Curl Rule:
If a current carrying conductor is imagined to be held in the right
hand such that the thumb points in the direction of the current,
then the tips of the fingers encircling the conductor will give the
direction of the magnetic lines of force.
Magnetic Field Lines due to current carrying conductor:
Direction of B is determined by Right Hand Screw Rule.
It is perpendicular to the plane of the diagram and entering into the plane at as shown in diagram.
I
B
B
I
I
B
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8. I I
Different views of direction of current and magnetic field due to circular loop of
a current carrying coil:
B
I
I
B B
Current moving in clock wise direction
representing the face towards us (Inwards) as
South pole of bar magnet
Current moving in anti-clock wise direction
representing the face towards right (outwards) as
North pole of bar magnet
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9. Magnetic Field due to a current carrying Solenoid:
I I
x
x
x
x
x x
x
TIP:
When we look at any end of the coil carrying current, if the current is in anti-clockwise
direction then that end of coil behaves like North Pole and if the current is in clockwise
direction then that end of the coil behaves like South Pole. Hence it behave like bar magnet.
B
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10. Force acting on a current carrying conductor:
1. A current carrying conductor is freely suspended from a stand
with the help of thread and connecting wires as shown in fig.
2. A horse shoe magnet is placed over the conductor at centre
such that, north pole on top and south pole at bottom and
direction of motion of conductor is noted.
3. The direction of poles are now reversed and the direction of
motion of conductor is noted.
4. The polarity of cell is reversed and above steps is repeated
and the direction of motion of conductor is noted in each
case.
5. The conclusion is drawn from the observations.
Conclusion: i) The direction of motion of conductor is towards
east, when the current is outward plane perpendicular with
direction of magnetic field from N â S and current moving into
the plane and direction of magnetic field is S â N.
ii) The direction of motion of conductor is towards west
for other two directions of current and MF.
ACTIVITY:
3 D view:
https://youtu.be/rtjGH0B-vVA
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11. FLEMINGâS LEFT HAND RULE:
I
Stretch first three fingers of your left hand
mutually perpendicular to each other such that,
fore (Index) finger represents direction of
magnetic field, middle finger represent direction
of current, then thumb finger show the direction
of force (motion) of the conductor.
Conclusion: i) The direction of motion of
conductor is towards east, when the current is
outward plane perpendicular with direction of
magnetic field from N â S and current moving into
the plane and direction of magnetic field is S â N.
ii) The direction of motion of conductor is
towards west for other two directions of current
and MF.
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12. ELECTRIC MOTOR:
AC MOTOR: DC MOTOR:
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13. It is a device which converts electrical energy (AC/DC current) into mechanical
energy.
Principle: When a current carrying conductor placed between magnetic field it will
undergo rotation based on Flemingâs left hand rule.
Construction: As shown in diagram all the components are placed and necessary
AC/DC current is given.
Working: When current is passed through armature in clock wise direction,
according to Flemingâs left hand rule, left part (towards North) of armature
will experience upward motion and right part will experience downward
motion and it starts rotating, due to commutators the direction of rotation is
such that it will be according AC/DC cycle which are in contact with metallic
(carbon) brush and hence to the source.
Conclusion: Electrical energy is converted into mechanical energy.
Application: Fan, mixer, blender, washing machine etc.
AC/DC MOTOR:
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14. The relative motion between closed conducting wire and magnet will induce
electric current in the coil without any electrochemical reaction.
Faradayâs Experiments:
Fig. having solenoid and magnet produce current whenever there is relative motion
between coil and magnet which is noticed in deflection of galvanometer needle.
Also notice that the direction of current is reversed when there is change in the pole
of the bar magnet and its relative motion with coil as we notice that, current moving
in anticlockwise represents North pole of magnet and in clockwise it will behave as
South pole of the magnet.
Faradayâs Electromagnetic Induction:
Current
direction
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15. Stretch first three fingers of your right hand
mutually perpendicular to each other such
that, fore (Index) finger represents
direction of magnetic field, middle finger
represent direction of current induced, then
thumb finger show the direction of force
(motion) of the conductor.
Flemingâs right hand rule:
Alternating current (AC) is time varying
current which varies sinusoidal or
cosinusoidal with time.
Direct Current (DC) is having fixed magnitude
and wonât change with time.
AC and DC current:
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16. ELECTRIC GENERATOR:
It is a device which converts mechanical energy into
electrical energy (AC/DC current).
Principle: When a coil is rotated between magnetic
field there will be induced current/emf based on
Electromagnetic Induction.
Construction: As shown in diagram all the components
are placed and necessary AC/DC current is drawn
across load resistor.
Working: When armature is rotated between strong
magnetic field according to Electromagnetic Induction
and Flemingâs right hand rule there will be induced
current/emf in the coil and it is drawn across resistor,
which are in contact with metallic (carbon) brush and
hence to the battery.
Conclusion: Hence the mechanical energy is converted
into electrical energy.
Load
Resistor
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17. ADVANTAGES OF AC OVER DC
1. The cost of producing AC much lesser than that of DC.
2. AC can be easily converted into DC using rectifier.
3. AC can be easily transmitted for long distances compared to DC.
4. AC can be controlled much easily compared to DC without much loss of energy.
DISADVANTAGES OF AC OVER DC
1. AC cannot be used in electrolysis as that of DC.
2. AC is more dangerous than DC.
3. AC will have more magnitude (Positive value) compared to DC magnitude.
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18. The electric circuit designed for the purpose of domestic use (house, factory, SSI etc) is
called domestic electric circuit.
DOMESTIC ELECTRIC CIRCUIT:
The electric circuit is having
Live wire ( +ve):
Neutral wire(- ve):
Earth wire (0 V):
Insulated colour wires,
Two circuits one of 15 A
rating fuse for Heavy
appliances such as Heater,
oven etc. and 5 A fuse for
bulb, fan etc.
The applied voltage across
mains is, 220 â 240 V in India
with 50 Hz frequency.
S1
S2 S3
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19. 1. Live wire: It is kept as positive with 220 V supply from mains.
2. Neutral wire: It is kept at 0 V w.r.t. live wire for completing the circuit
connection.
3. Earth wire: It is connected to earth through metallic wire which is at 0 V and
can allow the excess charges produced easily whenever electrical hazard
takes place.
4. Switch( S1, S2 âŚ) : It is controlling component which is connected in series
with live wire to operate appliances whenever needed.
5. Fuse: It is safety device which is connected in series with appliances with
suitable rating for easy melting and disconnection whenever there is short
circuit or overloading in circuit. It is made up of alloys of Al, Fe, Cu, Sn, Pb etc.
6. MCB (Miniature Circuit Breaker): Designed to break circuit during electrical
hazards based on electromagnetic induction or eddy current production.
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20. 7. Short Circuit: When live wire coincide with neutral wire directly (accidentally)
there will be sudden flow of charges from high potential to low potential
causing enormous heat according to Jouleâs heating effect in the circuit .
8. Over loading: When there are more number of appliances are connected in
parallel at a time the effective resistance will reduce too small giving the
condition of short circuiting called as overloading.
9. Electrical Hazard: It is electric shock which produce enormous heat which is
capable of burning whole domestic electric circuit due to short circuit or
overloading or failure in the earthing of appliances.
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21. SUMMARY:
1. Magnetic field and magnetic field line properties
2. Current carrying conductor and coil possess magnetic properties
3. Various laws and rules explaining the direction of magnetic field produced due to
current carrying conductor, such as right hand thumb rule.
4. When current appear to travel in anti clockwise direction in a closed coil it behave
like North pole, if it is clockwise it resembles South pole of a magnet
5. The combination of such closed loops form solenoid and when current is passed
through it behaves like bar magnet.
6. The direction of force experienced by current carrying conductor in uniform
magnetic field â Flemingâs left hand rule, its application in electric motors such as
grinder, fan, washing machine etc.
7. Production of induced current/ emf due to relative motion between coil and
magnet â Electromagnetic induction.
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22. 8. Current is induced in a coil when subjected rotation in a uniform magnetic field â
Flemingâs right rule
9. Application of EMI in producing current due to various sources â AC generation in
Hydroelectric power plants, wind mill etc.
10. Purposeful use of electricity using domestic electric circuit with proper safety
devices and precautions
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