Download Magnetic Effect of Current and Magnetis1

Magnetic Effect of Current and Magnetism
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Magnetic field. How can the direction of field lines at a place be determined?
Magnetic field lines do not intersect each other. Explain.
Properties of the Magnetic field lines
When an electric current is passed through any wire, a magnetic field is produced
around it. then why an electric iron connecting cables does not attract nearby iron
objects when electric current is switched on though it?
A freely suspended magnet always point in north-south direction. Explain
State and explain the clock face rule for determining the polarities of a circular wire
carrying current.
What are the factor affecting the strength of an electromagnet.
Difference between a bar magnet and electromagnet
What is solenoid? Diagram for magnetic field due to current carrying solenoid. Uses
of solenoid.
Difference between bar magnet and company Magnet
Clock face rule. The process of determining the polarities of a circular wire carrying
current through clock face rule.
What Type of core should be put inside a current carrying solenoid to make an
electromagnet?
As magnetic field has Magnitude as well as direction. Explain.
No two magnetic field lines are found to cross each other. Explain
Importance of MRI for human body
How to locate a current wire concealed in a wall.
Explain- No force acts on a current carrying conductor when it is parallel to the
magnetic field.
Explain Flemings’ left hand rule for the direction of force.
On what principal does motor work?
With diagram the working of electric motor?
How will you find the direction if a current carrying conductor is placed in a
perpendicular field.
Special features of commercial electric motor.
Example of electromagnetic induction
How can we increase the magnitude of current induced in the coil.
What is electric generator and its principal.
Two circular coils A and B are placed close to each other. If the current in coil A is
change, will some current be induced in coil B? Give reason.
AC generator and its diagram, explain its construction and working of AC generator
Why the direction of induced current in the coil of an AC generator changes after
direction showing the production of the coil.
What normally drives the alternators in a thermal power station? What fuels can be
used to heat water in the boiler?
A circuit has fuse of a 5 A. what is the maximum number of 100 W (220 V) bulbs that
can be safely used in the circuit?
How is earthing of electric appliances done?
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What type of electric fuse is used in electrical appliances like stereos? Explain with
diagram.
Difference between overloading and short- circuiting as used in domestic circuits.
An air-conditioner of 3.2 kW power rating is connected to a domestic electric circuit
having a current rating of 10 A. the voltage of power supply is 220 V. what will
happen when this air- conditioner is switched on? Explain your answer.
Go through the some questions given here as example and get an idea that how
questions can be framed
Q1. The correct field lines are
Q2. An electric current passes through a straight wire in the direction of south to
north. Magnetic compasses are placed at points A and B as shown in the figure. What
is your observation?
a. The needle will not deflect
b. Only one of the needles will deflect
c. Both the needles will deflect in the same direction
d. The needles will deflect in the opposite directions
Q3. Choose the incorrect statement from the following regarding magnetic lines of
field
a. The direction of magnetic field at a point is taken to be the direction in which the north
pole of a magnetic compass needle points
b. Magnetic field lines are closed curves
c. If magnetic field lines are parallel and equidistant, they represent zero field strength
d. Relative strength of magnetic field is shown by the degree of closeness of the field lines
Q4. What would be the effect of replacing ordinary bulbs with CFLs?
a. CFLs give less light than regular bulb hence room would be less bright
b. CFLs use less electricity hence electric bill will be reduced
c. CFLs produce more heat hence chances of fire will be increased
Q5. A coil of insulated copper wire is connected to a galvanometer forming a loop
and a magnet is
A: held stationary, B : moved away along its axis C : moved towards along its axis,
There will be induced current in
a. A only
b. A and B only
c. B and C only
d. A, B and C
Q6. If two circular coils can be arrange in any of the tree situations shown in the
diagram below, then their mutual induction will be….
a. Maximum in situation (a)
b. Maximum in situation (b)
c. Maximum in situation (c)
d. The same in all situations
Q7. The resistance of a copper wire 200 m long is 21 Q. if its thickness (diameter) is
0.44mm, its specific resistance is
a. 1.2 x 10~ 8 Q-m
b. 1.4 x 10~8 Q-m
c. 1.6 x 10”””Q-m
d. 1.8 x 10”8 Q-m
Q8. A magnetic field of 5 Tesla is produced by a long wire carrying a current of 5A at
a point distance 2 m from it. If the distance is made four-fold, the magnetic field will
be
a. 0.5 Tesla
b. 1.25 Tesla
c. 0.2 Tesla
d. 4 Tesla
Q9. A constant current flows in a horizontal wire in the plane of the paper from east
to west as shown below, the direction of magnetic field at a point will be north to
south
a. Directly above the wire
b. Directly below the wire
c. At a point located in the plane of the paper, on the north side of the wire
d. At a point located in the plane of the paper, on the south side of the wire
Q10. As shown in the diagram, there is a magnetic field within a region of space. The
magnetic field strength is the greatest at
a. P
b. Q
c. R
d. S
Q11. The direction of induced curent is obtained by
a. Fleming's left-hand rule
b. Maxwell's right-hand thumb rule
c. Ampere's rule
d. Fleming's right-hand rule
Q12. A soft iron bar is introduced inside a current carrying solenoid. The magnetic
field inside the solenoid
a. will become zero
b. will decrease
c. will increase
d. will remain unaffected
Q13. Which of the following diagrams correctly shows the magnetic field produced
by a current-carrying wire?