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Q1- A strong bar magnet is placed vertically above a horizontal wooden board. The magnetic lines of force will be :
A) only in horizontal plane around the magnet
B) only in vertical plane around the magnet
C) in horizontal as well as in vertical  planes around the magnet
D) in all planes around the magnet

Q2- The magnetic field lines produced by a bar magnet:
A) originate from the south pole and end at its north pole
B) originate from the north pole and end at its east pole
C) originate from the north pole and end at its south pole
D) originate from the south pole and end at its west pole

Q3- which of the following is not attracted by a magnet ?
A) steel
B) cobalt
C) brass
D) nickel

Q4- The magnetic field lines :
A) intersect at right angles to one another
B) intersect at an angle of 450 to each other
C) do not cross one anotherD) cross at an angle of 600 to one another

Q5- The north pole of earth’s magnet is in the: A) Geographical south B) Geographical east
C) Geographical west
D) Geographical north

 Q6- The axis of earth’s magnetic field is inclined with the geographical axis at an angle of about:
A) 50
B) 150
C) 250
D) 350

Q7- The shape of the earth’s magnetic field resembles that of an imaginary: A) U- Shaped Magnet
B) Straight conductor carrying current
C) Current carrying circular coil
D) Bar magnet

Q8- A magnet attracts:
A) plastics
B) any metal
C) aluminium
D) iron and steel

Q9- A plotting compass is placed near the south pole of a bar magnet the pointer of plotting compass will:
A) Point away from the south pole
B) Point Parallel to the south pole
C) Point towards the south pole
D) Point at right angles to the south pole

Q10- The metallic pointer of a plotting compass gets deflected only when it is placed near a bar magnet because the pointer has :
A) Electromagnetism
B) Permanent magnetism
C) Induced magnetism
D) ferromagnetism

Q11- Which of the following statements is incorrect regarding magnetic field lines?
A) The direction of the magnetic field at a point is taken to be the direction in which the north pole of the 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

Q12- The strength of the magnetic field between the polls of an electromagnet would be unchanged if:
A) Current in the electromagnet winding were doubled
B) Direction of current in electromagnet winding were reserved
C) Distance between the poles of electromagnet were doubled
D) Material of the core of electromagnet were changed

Q13- The magnetic field inside a long straight solenoid carrying current
A) is Zero
B) Decreases as we move towards its end.
C) Increases as we move towards its end.
D) Is the same at all points.

 Q14- Which of the following correctly describes the magnetic field near a long straight wire
A) The field consists of straight lines perpendicular to the wire
B) The field consists of straight line parallel to the wire
C) The field consists of radial lines originating from the wire
D) The field consists of concentric circles centred on the wire.

Q15-The north- south polarities of an electromagnet can be found easily by using:
A) Fleming’s right hand rule
B) Fleming’s left hand rule
C) Clock face rule
D) Left hand thumb rule

Q16- The direction of current in the coil at one end of an electromagnet is clockwise. This end of the electromagnet will be:
A) North pole
B) East pole
C) south pole
D) west pole

Q17- If the direction of electric current in a solenoid when viewed from a particular end is anti clockwise, then this end of solid noida will be:
A) west pole
B) south pole
C) north pole
D) east pole


Q18- The most suitable material for making the core of electromagnet is A) Soft iron
B) brass C) aluminium
D) steel

Q19- The magnetic effect of current was discovered by :
A) Maxwell B) Fleming
C) Oersted
D) Faraday

Q20- A Soft iron bar is inserted inside a current-carrying solenoid. The magnetic field inside the solenoid:
A) will decrease
B) will increase
C) will become zero
D) will remain the same

Q21- The magnetic field lines in the middle of the current-carrying solenoid are:
A) circles
B) spirals
C) parallel to the axis of the tube
D) perpendicular to the axis of the tube

Q22- The front face of a circular wire carrying current behaves like a north pole. The direction of current in this face of the circular wire is:
A) clockwise
B) downwards
C) anticlockwise
D) upwards

Q23- The back face of a circular loop of wire is found to be south magnetic pole. The direction of current in this face of the circular loop of wire will be:
A) towards south
B) clockwise
C) anticlockwise
D) towards north

Q24- In an electric motor the direction of current in the coil changes once in each
A) two rotations
B) one rotation
C) Half rotation
D) one-fourth rotation

Q25- The force experienced by a current carrying conductor placed in magnetic field is the largest when the angle between the conductor and the magnetic field is:
A) 450 B) 600
C) 900
D) 1800

Q26- The force exerted on a current carrying wire placed in magnetic field is zero when the angle between the wire and the direction of magnetic field is:
A) 450 B) 600
C) 900
D) 1800

Q27- An electric motor is a device which transforms
A) Mechanical energy to electrical energy
B) Heat energy to electrical energy
C) Electrical energy to heat energy only
D) Electrical energy to mechanical energy

 Q28- A magnetic field exerts no force on .
A) an electric change moving perpendicular to its direction
B) an magnetised iron bar
C) a stationary electric charge D) a magnet

Q29- A rectangular coil of copper wire is rotated in a magnetic field. The direction of induced current changes once in each:
A)two revolutions
B) one revolution
C) half revolution
D) one-fourth revolution

Q30- The phenomenon of electromagnetic induction is 
A) The process of charging a body
B) The process of generating magnetic field due to a current passing through a coil  C) Producing induced current in a coil due to relative motion between a magnet and the coil     D) The process of rotating a coil of an electric motor         

Q31- The device used for producing electric current is called a:
A) Generator
B) Galvanometer
C) Ammeter
D) Motor

Q32- The essential difference between an AC generator and a DC generator is that
A) AC Generator has an electromagnet   while a DC generator has permanent magnet
B) DC generator will generate a higher voltage
C) AC generator will generate a higher voltage
D) AC generator has slip rings while the DC generator has a commutator

Q33- Each one of the following changes will increase emf (or voltage) in a simple generator except:
A) Increasing the number of turns in armature coil
B) winding the coil on a soft iron armature
C) Increasing the size of the gap in which the armature turns
D) Increasing the speed of rotation

Q34-The north pole of a long bar magnet watch pushed slowly into a short solenoid connected to a galvanometer. The magnet watch held stationary for a few seconds with the north pole in the middle of the solenoid and then withdrawn rapidly. The maximum deflection of the galvanometer was observed when the magnet was:
A) Moving towards the solenoid
B) Moving into Solenoid
C) At rest inside the solenoid
D) Moving out of the solenoid

Q35- An electric generator converts
A) Electrical energy into mechanical energy
B) Electrical energy Into chemical energy
C) Electrical energy into chemical energy
D) Mechanical energy into electrical energy

Q36-A DC generator is based on the principle of
A) Electrochemical induction
B) Electromagnetic induction
C) Magnetic effect of current
D) Heating effect of current

Q37- An Induced current is produced when a magnet is moved into a coil. The magnitude of induced current does not depend on A) The speed with the magnet is moved
B) The number of turns of the coil.
C) The resistivity of the wire of the coil
D) The strength of the magnet

Q38- The frequency of direct current (DC) is:
A) 0 Hz
B) 50 Hz
C) 60 Hz
D) 100 Hz

Q39- The frequency of alternating current (A.C.) supply in india is
A) 0 Hz
B) 50 Hz C) 60 Hz
D) 100 Hz

Q40- At the time of short circuit the current in the circuit :
A) Reduces substantially
B) Does not change
C) Increases heavily
D) Varies continuously

Q41- A 1.25 kW heater works on a 220V mains supply. What current rating would a suitable fuse have?
A) 2 A
B) 5 A
C) 10 A
D) 13 A

Q42- The maximum number of 40 W tube lights connected in parallel which can safely be run from a 240 V supply with a 5 A fuse is
A) 5
B) 15
C) 20
D) 30

Q43- In normal use, a current of 3.5 A flows through a hair dryers choose a suitable fuse from the following :
A) 3 A
B) 5 A C)10 A
D) 30A

Q44- which one of the following statements is not true? 
A) In a house circuit, lamps are used in parallel
B) Switches, fuse and circuit breakers should be placed in the neutral wire
C) An electric iron has its earth wire connected to the metal case to prevent the users receiving a shock
D) When connecting a three core cable to a 13A three-pin plug the red wire goes to the live pin.

Q45- A car headlamp of 48W works on the car battery of 12V. The correct fuse for the circuit of this car headlamp will be:
A) 5 A
B) 10 A
C) 3 A
D) 13 A


Q46- A 3-Pin mains plug is fitted to the cable for a 1kW electric kettle to be used on a 250 a.c. supply. Which of the following statements is not correct? A) The fuse should be fitted in the live wire
B) A 13 A fuse is the most appropriate value to use
C) The neutral wire is coloured black
D)  The green wire should be connected to the earth pin.

Q47- A TV set consumes an electric power of 230 watts and runs on 230 volts main supply. The correct fuse for this TV set is:
A) 5 A
B) 3 A
C) 1 A
D)  2 A

Q48- Circuit breaker device which can be used in place of fuse in domestic electric wiring is called 1, CBD 2, DCB 3 MCD 4. MCB

Q49- An MCB which cuts off the electricity supply in case of short circuiting or overloading works on the: A)Chemical of current
B)Heating effect of current
C)Magnetic effect of current
D)Electroplating effect of current 


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