## Labels

### 10+2 PSEB EXAM : PHYSICS SEPTEMBER SOLVED PAPER

Time 1.5 hr Class XII

Sub Physics MM 35 September 2021

NOTE: 1. Question paper has 35 multiple choice questions.

2. Each question is compulsory.

3. Q.1 to 11 are knowledge based questions, Q.12 to 24 are understanding based questions & Q.25 to 35 are application based questions.

## Q1 The angle between the electric dipole moment (P⃗ ) and electric field (E⃗ ) due to the dipole at a point on its axial and equatorial lines respectively are

• a) 0^{0} , 180^{0}
• b) 90^{0} , 180^{0}
• c) 180^{0} , 0^{0}
• d) 0^{0} , 90^{0}

• a) 0^{0} , 180^{0}

## Q2 Unit of capacity of conductor is farad. 1 farad(F) is equal to

• (a)1F = \frac{1 coloumb}{1ampere}
• (b) 1F = \frac{1 ampere }{1 coloumb}
• (c) 1F = \frac{1 coloumb}{1 vol.t}
• (d) 1F = \frac{1 vol.t}{1 coloumb}

• (c) 1F = \frac{1 coloumb}{1 vol.t}

## Q3 The material of wire of potentiometer is :

• (a) Copper, because it has high conductivity
• (b) Steel, because it is very hard and rust free.
• (c) Manganin, because of high resistivity and low temperature coefficient of resistivity.
• (d) Aluminium, because it is a good conductor and cheaper than copper

• (c) Manganin, because of high resistivity and low temperature coefficient of resistivity.

## Q4 A cyclotron cannot be used to accelerate the electrons because

• (a) Electrons are very heavy and they cannot rotate with the frequency of oscillating electric field.
• (b) Electrons are negative charged particles. Therefore, they do not get accelerated inside an electric field.
• (c) Electrons are very light particles, they are accelerated at once. They go out of step with oscillating electric field and hence cannot be accelerated.
• (d) Electrons mass changes into energy by Einstein formula E = mc2 and therefore they disappear from the system.

• (c) Electrons are very light particles, they are accelerated at once. They go out of step with oscillating electric field and hence cannot be accelerated.

## Q5 The angle of dip at the magnetic equator and magnetic poles respectively is

• a) 0^{0} , 45^{0}
• b) 45^{0} , 45^{0}
• c) 90^{0} , 0^{0}
• d) 0^{0} , 90^{0}

• d) 0^{0} , 90^{0}

• (a) 0 A
• (b) 1A
• (c) 2A
• (d) 3A

• (b) 1A

## Q7 The magnetic lines of force around an infinitely long straight current carrying conductor are

• (a) Concentric circles around conductor
• (b) Parallel to length of conductor
• (c) Perpendicular to length of conductor
• (d) None of these

• (a) Concentric circles around conductor

## Q8 A metal rod of length 'l' moves with velocity 'v' along the direction of uniform magnetic field B⃗ , then the motional EMF developed across the ends of the rod is equal to

• (a) e = B𝑙v
• (b) e = 0
• (c) e = B𝑙/v
• (d) e = Bv/l

• (a) e = B𝑙v

## Q9. Eddy current may be reduced by using:

• (a) thick piece of plastic
• (b) laminated core of soft iron
• (c) thick piece of cobalt
• (d) thick piece of nickel

• (b) laminated core of soft iron

## Q10 . Effective resistance of an electric circuit to alternating current, arising from combined effect of ohmic resistance and reactance is called:

• (a) Capacitance
• (b) Tolerance
• (c) Impedance
• (d) Inductance

• (c) Impedance

## Q11 Which of the following radiations are used respectively for Lasik eye surgery and to take photograph during the conditions of fog and smoke?

• (a) Visible rays, X rays
• (b) Ultraviolet rays, Infrared rays
• (c) Infrared Rays, Ultraviolet rays
• (d) Microwaves, Gamma rays

• (b) Ultraviolet rays, Infrared rays

## Q12 The equipotential surfaces produced by single positive or negative charge are concentric spheres. The gap between these spheres as we move away from charge

• (a) decreases
• (b) remains same
• (c) increases
• (d) first increases and then decreases

• (c) increases

• (a) 4R, ρ/2
• (b) 4R, 4 ρ
• (c) 4R, ρ
• (d) R/4, 2ρ

• c) 4R, ρ

## Q14 The sensitivity of a potentiometer can be increased by

• (a) Increasing length of wire and decreasing resistance in series with the potentiometer wire
• (b) Decreasing length of wire and decreasing resistance in series with the potentiometer wire
• (c) Increasing length of wire and increasing resistance in series with the potentiometer wire
• (d) Decreasing length of wire and increasing resistance in series with the potentiometer wire

• (c) Increasing length of wire and increasing resistance in series with the potentiometer wire

## Q15 . A compass needle does not work at magnetic poles because

• (a) Compass needle is free to move in a vertical plane only
• (b) Compass needle is free to move in a horizontal plane only
• (c) Compass needle cannot measure earth magnetic field because it is very weak.
• (d) Weight of compass needle becomes more at poles.

• (b) Compass needle is free to move in a horizontal plane only

## Q16 The resistance of voltmeter, ammeter and galvanometer in the increasing order can be written as

• (a) Rvoltmeter < Rammeter < Rgalvanometer
• (b) Rammeter < Rvoltmeter < Rgalvanometer
• (c) Rvoltmeter < Rgalvanometer < Rammeter
• (d) Rammeter < Rgalvanometer < Rvoltmeter

• (d) Rammeter < Rgalvanometer < Rvoltmeter

## Q17 The earth’s core has iron but it is not regarded as source of earth’s magnetism because:

• (a) Iron does not show magnetic properties
• (b) Temperature of earth’s core is very high and at this temperature iron does not remain ferromagnetic.
• (c) Iron is a superconducting material
• (d) None of these

• (b) Temperature of earth’s core is very high and at this temperature iron does not remain ferromagnetic.

## Q18 Magnetic field due to a current carrying conductor is zero:

• (a) along a line perpendicular to the wire
• (b) along the axial line of the wire
• (c) along a line inclined 45° to the wire
• (d) it can never be zero

• (b) along the axial line of the wire

## Q19. A lamp is connected in series with a capacitor to a high frequency AC source. Then it is connected directly to the same source which is true statement about this.

• (a) Lamp will glow more brightly when the capacitor is in series with it.
• (b) Lamp will glow more brightly on connecting it directly to the source.
•  (c) Lamp glows with same brightness in both cases.
• (d) Brightness of glow of bulb does not depend upon capacitive reactance.

• (b) Lamp will glow more brightly on connecting it directly to the source.

## Q20 . The current in series LCR circuit will be maximum when angular frequency ω is

• (a) as large as possible
• (b) equal to natural frequency of LCR circuit
• (c) (LC)^{1/2}
•  (d) 1/LC

• (b) equal to natural frequency of LCR circuit

## Q21 The current flowing from A to B is increasing as shown in the figure. The direction of the induced current in the loop is

• (a) clockwise
• (b) anticlockwise
• (c) straight line
• (d) no induced e.m.f. produced

• (a) clockwise

## Q22 Gamma rays are used in radiation therapy in order to treat cancer because

• (a) Gamma rays have magical therapeutic properties.
• (b) Gamma rays travel faster then other electromagnetic radiations.
• (c) Gamma rays are highly energetic and can destroy cancer cells.
• (d) None of these

• (c) Gamma rays are highly energetic and can destroy cancer cells.

## Q23 The equation of electric field part of an electromagnetic wave is given by 𝐄⃗ = [ 3.1 cos { 1.8 y + 5.4 × 10^{6} t } ] i(unit vector i) , the directions of oscillation of electric field, magnetic field and propagation of wave respectively are

• (a) x axis, y axis, +z axis
• (b) z axis, y axis, +x axis
• (c) x axis, z axis, +y axis
• (d) x axis, z axis, −y axis

• (d) x axis, z axis, −y axis

## Q24 The electromagnetic spectrum in the increasing order of frequency is given as Radio waves, microwaves, Infrared rays, visible rays, Ultraviolet rays, X-rays, Gamma rays. Which physical quantity is same for all these waves in vacuum?

• (a) wavelength
• (b) speed
• (c) energy
• (d) all of these

• (b) speed

• a) 9.2 F
• b) 3.7 F
• c) 7.2 F
• d) 2.7F

• c) 7.2 F

• (a) 4
• (b) 1/4
• (c) 1
• (d) 2

• (b) 1/4

• (a) 2:1
• (b) 1:1
• (c) 1:4
• (d) 1:2

• (a) 2:1

## Q28 A Galvanometer of resistance 12 ohm gives full deflection for 8 mA. It can be converted into voltmeter of range 0-32 V with help of resistance of:

• (a) 5988 ohm
• (b) 3988 ohm
• (c) 2500 ohm
• (d) 4000 ohm

• (b) 3988 ohm

## Q29. In the magnetic meridian of a certain place, the horizontal component of earth’s magnetic field is 0.26 G and the dip angle is 60^{0} , the vertical component of earth’s magnetic field at that place will be (G → gauss)

• (a) \frac{0.26}{\sqrt{3}}G
• (b) \sqrt{3}G
• (c) 0.52 G
• (d) 0.13 G

• (b) \sqrt{3}G

## Q30 . Magnetic susceptibility of magnesium at 300K of temperature is 1.2 × 10^{-5} , the magnetic susceptibility of magnesium at 30K of temperature will be

• (a) 1.2 × 10^{-3}
• (b) 1.2 × 10^{-4}
• (c) 1.2 × 10^{-5}
• (d) 1.2 × 10^{-6}

• (b) 1.2 × 10^{-4}

## Q31 The smallest value of magnetic dipole moment  𝝁l  of an atom due to orbital motion of an electron in first orbit is called Bohr Magneton 𝜇B. The value of Bohr Magneton is equal to

• a) 𝝁B=9.27x 10^{-24}Am^{2}
• b) 𝝁B=1.38x 10^{-23}Am^{2}
• c) 𝝁B=6.022x 10^{23}Am^{2}
• d) 𝝁B=1.6x 10^{-19}Am^{2}

• a) 𝝁B=9.27x 10^{-24}Am^{2}

## Q32 The magnetic flux passing through a coil changes from 6×10^{-3} Wb to 7.2×10^{-3} Wb in 0.02s.Calculate the induced e.m.f.:

• (a) -6×10^{-2}V
• (b) 8×10^{-2}V
• (c) 2×10^{-2}V
• (d) -3×10^{-2}V

• (a) -6×10^{-2}V

• (a) 0.5 A
• (b) 2.5 A
• (c) 5 A
• (d) 1.5 A

• (b) 2.5 A

• (a) 50 π H
• (b) 100 π H
• (c) 75 π H
• (d) 60 π H

• (b) 100 π H

## Q35 Find the wavelength of electromagnetic waves of frequency 6×10^{12} Hz in free space having speed of 3 × 10^{8} m/s in free space

• a) 6 x 10^{-5}
• b) 5 x 10^{-5}
• c) 2.5 x 10^{-5}
• d) 1.5 x 10^{-5}

• b) 5 x 10^{-5}

## Q1 The definition of one atomic mass unit and its value is

• (a) 1/12th the mass of an atom of oxygen-16, 1amu = 1.6 × 10^{-19} Kg
• (b) 1/16th the mass of an atom of carbon-12, 1amu = 9.1 × 10^{-31} Kg
• (c) 1/12th the mass of an atom of carbon-12, 1amu = 1.66 × 10^{-27}Kg
• (d) The mass of helium nucleus, 1amu = 3.2 × 10^{-27} Kg

• (c) 1/12th the mass of an atom of carbon-12, 1amu = 1.66 × 10^{-27}Kg

## Q2  Which of the following quantity is vector quantity?

• (a) Density
• (b) angular velocity
• (c) Energy
• (d) angular frequency

• (b) angular velocity

## Q3  Which of the following quantities remains constant in a projectile motion?

• (a) Speed of body
• (b) acceleration acting on the body
• (c) vertical component of velocity
• (d) linear momentum of body

• (b) acceleration acting on the body

## Q4 The working of rocket is based on the principle of

• (a) Newton's first law
• (b) inertia of rest
• (c) conservation of linear momentum
• (d) none of these

• (c) conservation of linear momentum

## Q5  The component of contact force in the direction parallel to the surface of contact of two bodies and perpendicular to the surface are called

• (a) normal reaction, frictional force
• (b) frictional force, normal reaction
• (c) centripetal force, centrifugal force
• (d) centrifugal force, centripetal force

• (b) frictional force, normal reaction

## Q6 A car accelerates on a horizontal road due to the force exerted by

• (a) the engine of the car
• (b) the driver of the car
• (c) the earth gravitational force
• (d) the friction between tyres and road

• (d) the friction between tyres and road

## Q7  A body of certain mass is lifted upwards from ground to a certain height, the work done by the gravitational force and applied force respectively are

• (a) positive, negative
• (b) negative, positive
• (c) positive, positive
• (d) negative, negative

• (b) negative, positive

• (a) 0,1
• (b) 0,0
• (c) 1,1
• (d) 1,0

• (d) 1,0

## Q9.  The center of mass of two non identical particle system

• (a) always lies in between two particles and on the line joining them
• (b) always lies at the center of two particles
• (c) may lie outside the two particle system but on the line joining them
• (d) always lies nearer the lighter particle

• (a) always lies in between two particles and on the line joining them

## Q10 Angular momentum has the same unit as

• (a) Impulse × distance
• (b) Linear momentum × time
• (c) Work × frequency
• (d) Power × distance

• (a) Impulse × distance

## Q11 In the absence of external torque acting on a rotating body, which of the following quantities can change?

• (a) Angular momentum
• (b) Angular velocity but not moment of inertia
• (c) Moment of inertia but not angular velocity
• (d) Both angular velocity and moment of inertia

• (d) Both angular velocity and moment of inertia

## Q12  The Vander Wall’s equation for an ideal gas is given by (P + a/V^{2} )(V- b) = RT, where P = pressure, V = volume, T = temperature, R = universal gas constant, a and b are constants. The dimensions of a and b in this equation are

• (a) [a] = L^{3}  [b], ML^{5} T^{-2}
• (b) [a] = L^{3}  [b], ML^{-3} T^{-2}
• (c) [a] = ML^{5} T^{-2}  [b] = L^{3}
• (d) [a] = ML^{3} T^{-2}  [b] = L^{5}

• (b) [a] = ML^{5} T^{-2}  [b] = L^{3}

## Q13  . A person starts his journey from his home at 9.00 a.m.to his office and came back to his home at 5.00 p.m. His office is 20 km from his home, then the displacement and distance covered in his complete journey are:

• (a) 20 km, 0 Km
• (b) 0 km, 20 Km
• (c) 40 km, 0 Km
• (d) 0 km, 40 Km

• (d) 0 km, 40 Km

## Q14 Which of the following statement for an object in uniform motion is not true?

• (a)The object must be moving in straight path along same direction
(b) The object covers equal displacements in equal intervals of time
• (c) The velocity of object changes by equal amounts in equal intervals of time like free fall under gravity.
• (d) The acceleration of object must be zero

• (c) conservation of linear momentum

## Q15  When a car moving in a fixed direction accelerates

• (a) The frictional force acts on it in the direction opposite to the direction of motion
• (b) The frictional force acts on it in the same direction as direction of motion
• (c) Frictional force is not required. The engine of the car gives the force needed.
• d) No force is required due to inertia of motion. The car accelerates by itself

• (b) The frictional force acts on it in the same direction as direction of motion

## Q16 If a body is stationary then

• (a) there is no force acting on it
• (b) the forces acting on it are not in contact with it
• (c) the combination of forces acting on it balance out
• (d) the body is in vacuum

• (c) the combination of forces acting on it balance out

## Q17  The restoring force produced in a spring is a conservative force. It means

• (a) Work done by spring force depends only on the initial and final positions.
• (b) Work done by spring force depends on the path between initial and final positions.
• (c) Work done by spring force in a cyclic process is non zero.
• (d) This statement is false. Spring force is a non conservative force

• (b) Work done by spring force depends on the path between initial and final positions.

## Q8 A man pushes a wall normally and fails to displace it but himself gets displaced by 2 m away from wall against frictional force between his feet and ground. Work done by wall on him is:

• (a) zero
• (b) negative
• (c) positive
• (d) depends on the frictional force between the wall and hands of the

• (c) positive

## Q19.  Four particles given below have same linear momentum, which has maximum kinetic energy?

• (a) proton
• (b) electron
• (c) deutron
• (d) alpha particle

• (b) electron

## Q20 In which of the following motions momentum changes but K.E. does not change?

• (a) A freely falling body
• (b) A body moving in uniform motion
• (c) A body vertically thrown upwards
• (d) A body moving in uniform circular motion

• (d) A body moving in uniform circular motion

## Q21 The casing of a rocket in flight burns up due to friction. At whose expense is the heat energy required for burning obtained?

• (a) The kinetic energy of rocket
• (b) Energy given by atmosphere
• (c) Energy given by burning fuel
• (d) The potential energy of the rocket

• (a) The kinetic energy of rocket

## Q22  When perfectly inelastic collision between two objects takes place, then during the collision

• (a) Linear momentum remains conserved.
(b) Kinetic energy remains conserved.
• (c) Both kinetic energy and linear momentum remain conserved.
• (d) Neither kinetic energy nor linear momentum remains conserved.

• (a) Linear momentum remains conserved.

## Q23  The angular velocity of a planet revolving in an elliptical orbit around the sun increases, when it comes near the sun and vice-versa. This process better explained on the basis of law of conservation of:

• (a) Mass
• (b) Linear Momentum
• (c) Angular Momentum
• (d) Energy

• (c) Angular Momentum

## Q24 A cylinder rolls down an inclined plane without slipping as shown. The work done against friction during rolling motion is

• (a) always positive
• (b) always negative
• (c) zero
• (d) first positive and then negative

• (c) zero

## Q25   The temperatures of two bodies measured by a thermometer are t1 = 200^{C} ± 0.50^{C} and t2 = 500^{C} ± 0.50^{C}. The temperature difference t = t2 – t1 between them is given by

• (a) t = 30 0^{C} ± 0.5 0^{C}
• (b) t = 70 0^{C}± 0.5 0^{C}
• (c) t = 700^{C}± 1.00^{C}
• (d) t = 300^{C}± 1.00^{C}

• (d) t = 30oC ± 1.0oC

• a) 0.1s
• (b) 0.2s
• (c) 0.3s
• (d) 0.4s

• (b) 0.2s

## Q27 The angle made by vector 𝐴⃗⃗ = 2𝑖̂+ 𝑗̂ with x axis is

• (a) tanθ = 0.5
• (b) tanθ = 2
• (c) tanθ = √5
• (d) tanθ = √ 2/5

• (a) tanθ = 0.5

## Q28 At what angle to the horizontal should an object be projected so that the maximum height reached is equal to the horizontal range?

• (a) tan θ = 1/4
• (b) tan θ = 1/2
• (c) tan θ = 4
• (d) tan θ = 2

• (c) tan θ = 4

## Q29.  A rocket with a lift – off mass 3.5×10^{4} kg is blasted upwards with an initial acceleration of 10 ms^{-2} . Then, the initial thurst of the blast

• (a) 3.5×10^{5} N
• (b) 7.0×10^{5} N
• (c) 14.0×10^{5} N
• (d)1.75×10^{5}N

• (b) 7.0×10^{5} N

## Q30 Determine the maximum acceleration of the train in which a box lying on its floor will remain stationary. Given that the coefficient of static friction between the box and train’s floor is 0.15. Take g = 10ms^{-2}

• (a) 0.5 ms^{-2}
• (b) 1.0 ms^{-2}
• (c) 2.5 ms^{-2}
• (d) 1.5 ms^{-2}

• (d) 1.5 ms^{-2}

• (a) – 50 J
• (b) – 550 J
• (c) – 750 J
• (d) – 200 J

• (c) – 750 J

## Q32  A particle of mass M is moving in a horizontal circle of radius R with uniform speed v. When it moves from one point to a diametrically opposite point, it’s

• (a) K.E changes by \frac{1}{2}mv^{2}
• (b) linear momentum does not change
• (c) linear momentum changes by 2 M v
• (d) K.E changes by mv^{2}

• (c) linear momentum changes by 2 M v

## Q33  How much energy is released, when 1mg of uranium is completely destroyed in an atom bomb.

•  (a) 7×10^{10} J
• (b) 8×10^{10} J
• (c) 9×10^{10} J
• (d) 5×10^{10} J

• (c) 9× 10^{10} J

## Q34 A solid cylinder of moment of inertia 0.625 kg m^{2}  rotates about its axis with angular speed 100 rads^{-1}. What is the magnitude of angular momentum of the cylinder about its axis?

• (a) 62.5 kgm^{2}s^{-1}
• (b) 625×104 kgm^{2}s^{-1}
• (c) 6.25 kgm^{2}s^{-1}
• (d) 625×105kgm^{2}s^{-1}

• (a) 62.5 kgm^{2}s^{-1}

## Q35  The sun rotates around itself in 27 days, if it were to expand to twice its present diameter, what would be its new period of revolution?

• (a) 27 days
• (b) 54 days
• (c) 81 days
• (d) 108 days

• (d) 108 days

### Current Electricity : MCQ on Current Electricity

The branch of Physics, which deals with the study of charges in motion is called Current Electricity.

Electric Current :- It is defined as the rate of flow of charge across any cross-section of conductor.

If a charge ‘q’ flows across any cross-section in ‘t’ second ,current ‘i’ is given by I= q/t

I= ne/t

Q1 S.I Unit of Electric motive force is

• Coulomb
• Ampere
• Volt
• Coulomb/Ampere

• Volt

Q2 Electromotive force .............potential difference.

• may be equals to
• may be greater than
• both (a) and (b)
• none of these

both (a) and (b)

Q3 A wire is carrying a current. Is it charged?

• Yes,
• No

No

(Electric current is the flow of free electrons in the conductors. At any instant, the no. of electrons leaving the wire is always equal to the no. of electrons flowing from the battery into it. Hence the net charge on the wire is zero.)

Q4 Electric current is a .................. quantity.

• Scalar
• Vector
• Tensor
• None of the above

• Scalar

Q5 S.I Unit of Electric current is ...

• Coulomb
• Ampere
• Tesla
• Coulomb/Ampere

• Ampere

Q6 One Ampere =.................................... stat ampere.

• 3x10^{19}
• 3x10^{9}
• 2.25x 10^{19}
• None of these

• 3x10^{19}

Q7 How many electrons passes in one second when current is 1A.

• 5.26 × 10^{18}
• 6.25 × 10^{25}
• 5.26 × 10^{19}
• 6.25 × 10^{19}

• 6.25 × 10^{25}

Q8 The relaxation time in conductors:

• Increases with increase in temperature
• Decreases with the increases of temperature
• It does not depend on temperature
• Changes suddenly at 400 Kelvin.

• Decreases with the increases of temperature.

Q9 According to Ohm’s Law

• V is directly proportional to I
• V is inversely proportional to I
• V is directly proportional to √I
• All of the above.

• V is directly proportional to I

Q10 Ohm's law is applicable to

• Semiconductors
• Vacuum tubes
• Carbon resistors
• None of these

• None of these

### MAGNETIC EFFECT OF CURRENT : MCQ ON MAGNETIC EFFECT OF CURRENT UNIT 3

Magnetic Effects of Current: MCQ ON Moving Charges and Magnetism

MAGNETIC EFFECT OF CURRENT   : MCQ ON AMPERE'S CIRCUITAL LAW

MAGNETIC EFFECT OF CURRENT   : MCQ MOTION OF CHARGE IN MAGANETIC FIELD

MAGNETIC EFFECT OF CURRENT  : MCQ ON SOLENOID

MAGNETIC EFFECT OF CURRENT ; MCQ ON FORCE ON CURRENT CARRYING CONDUCTOR

MAGNETIC EFFECT OF CURRENT ; MCQ ON GALAVANOMETER, AMMETER, VOLTMETER

MAGNETIC EFFECT OF CURRENT  ; MCQ ON MAGNETIC MATERIALS SET 1

MAGNETIC EFFECT OF CURRENT  :MCQ ON MAGNETIC MATERIALS SET 2

MAGNETIC EFFECT OF CURRENT  :MCQ ON MAGNETIC MATERIALS SET 3

MAGNETIC EFFECT OF CURRENT MCQ ON MAGNETIC MATERIALS SET 4

MAGNETIC EFFECT OF CURRENT; MCQ ON MAGNETIC MATERIALS SET

MCQ ON UNIT 1 FRICTIONAL ELECTRICITY

## Q1 Basic source of magnetism is

• (a) Charged particles alone
• (b) movement of charged particles
• (c) magnetic dipoles
• (d) magnetic domains

• (b) movement of charged particles

## Q2 A charge q is moving in a magnetic field, then the magnetic force does not depend upon

• (a) Charge
• (b) mass
• (c) velocity
• (d) magnetic field

• (b) mass

## Q3 The ratio of intensity of magnetization to the magnetizing force is called____

• a) Coercivity
• b) Hysteresis
• c) Magnetic susceptibility
• d) Magnetic Moment

• c) Magnetic susceptibility

## Q4 If magnetic moment of a substance is zero, then substance is

• (a)Diamagnetic
• (b) paramagnetic
• (c) ferromagnetic
• (d) antiferromagnetic

• (a)Diamagnetic

## Q5 Magnetic susceptibility for diamagnetic material is

• (a) Small and negative
• (b) small and positive
• (c) large and positive
• (d) large and negative

• (a)Small and negative

## Q6 Which of the following is diamagnetic substance

• (a)Nickel
• (b) cobalt
• (c) platinum
• (d) water

• (d) water

## Q7  A bar of paramagnetic material is placed in a strong external magnetic filed. Then, the field inside it is likely to

• (a) Remain the same
• (b) increase
• (c) vanish completely
• (d) decrease

• (b) increase

## Q8 Permeability of paramagnetic substances is

• (a) Zero
• (b) Unity
• (c) More than unity
• (d) Less than unity

• (c) More than unity

• a) True
• b) False

• a) True

• a) True
• b) False

b) False

## Q1 The factors on which one magnetic field strength produced by current carrying solenoids depends are

• (a) Magnitude of current
• (b) Number of turns
• (c) Nature of core material
• (d) All of the above

• (d) All of the above

## Q2 The magnetic field produced due to a solenoid is same as that produced by a....

• a) Bar magnet
• b) Electromagnet
• c) semi- circular coil containing current
• d) None of these

• a) Bar magnet

## Q3  A magnetic dipole is placed in a uniform magnetic fields, "B". At what angle magnetic dipole to be placed  in magnetic field so that  the potential energy is minimum

• a) 90^{0}
• b) 30^{0}
• c) 45^{0}
• d) 0^{0}

• d) 0^{0}

## Q4 The small angle between magnetic axis and geographic axis at a place is called

• (a) Magnetic inclination
• (b) Magnetic dip
• (c) Magnetic declination
• (d) None of the above

• (c) Magnetic declination

## Q5 Horizontal component of earth at a place is 3.2 x 10^{-5}T, and angle of dip is 60^{0} The resultant intensity of earth’s field at the place is

• a) 3.2 x 10^{-5}T
• b) 1.6 x 10^{-5}T
• c) 6.4 x 10^{-5}T
• d) 12.8 x 10^{-5}T

• c) 6.4 x 10^{-5}T

## Q6 Isogonic lines on magnetic map represent lines of

• (a) Zero declination
• (b) Equal declination
• (c) Equal dip
• (d) Equal horizontal field

• (b) Equal declination

## Q7  At magnetic poles which out of following is zero

• (a) Horizontal component (H) of earth's magnetic field
• (b) Vertical component of earth's magnetic field
• (c) Total strength of earth’s magnetic field(R)
• (d) Magnetic declination

• (a) Horizontal component (H) of earth's magnetic field

## Q8 At a certain place, the horizontal component of earth’s magnetic field is √3 times the vertical component. The angle of dip at that place is

• a) 90^{0}
• b) 30^{0}
• c) 45^{0}
• d) 0^{0}

• b) 30^{0}

• a) True
• b) False

• a) True

## Q10 At a particular place, horizontal and vertical components of earth’s magnetic field are equal. The angle of dip at that place is

• a) 90^{0}
• b) 30^{0}
• c) 45^{0}
• d) 0^{0}

• c) 45^{0}

## Q1 Magnetic field intensity at a point on the axial line of the magnet various with distance 'r' of the point from the center of the bar magnet as

• (a) r^{1}
• (b) r^{2}
• (c) r^{-1}
• (d) r^{-3}

• (d) r^{-3}

## Q2 Suppose magnetic field intensity at a distance r from the center of a short bar magnet on the axial live is B. Then magnetic field intensity at a distance r from the bisector of the bar magnet is.

• a) B
• b) 2B
• c) B/2
• d) None of these

• c) B/2

• a) m/l
• b) 2M/л
• c) m
• d) M

• b) 2M/л

## Q4 If magnetic length of a bar magnet is 'x' and the geometrical length of the bar magnet is 'y', then:

• a) x = y
• b) x > y
• c) x < y
• d) None of these

• c) x < y

## Q5 SI units of magnetic dipole moment of a bar magnet are

• a) Am^{2}
• b) Am^{-1}
• c) Am^{-2}
• d) A^{-1}m

• a) Am^{2}

• a) F
• b) F/4
• c) 2F
• d) F/2

• a) F

• a) True
• b) False

• a) True

## Q8 What is the net magnetic flux through a closed surface?

• a) Positive
• b) Negative
• c) Zero
• d) Depends on the nature of the surface

• c) Zero

## Q9.  ‘X’ is the product of the pole strength of either magnetic pole and the magnetic length of the magnetic dipole. Identify X.

• a) Magnetic dipole
• b) Magnetic dipole moment
• c) Magnetic pole strength
• d) Magnetic dipole length

• b) Magnetic dipole moment

## Q10 What is the torque exerted by a bar magnet on itself due to its field?

• a) Maximum
• b) Zero
• c) Minimum
• d) Depends on the direction of the magnetic field

• b) Zero,
• A bar magnet does not exert a force or torque on itself due to its field. But an element of a current-carrying conductor experiences forces due to another element of the conductor. So, the torque exerted by a bar magnet on itself is zero.

• (a) Bqv
• (b) B/qv
• (c) Zero
• (d) q/Bv

• (c) Zero

## Q2 The dimensions of magnetic field intensity are

• a) M^{1}L^{1}T^{-1}
• b) M^{1}T^{-2}A^{-1}
• c). M^{1}T^{-2}A^{-2}
• d). M^{1}T^{-1}A^{-1}

• b) M^{1}T^{-2}A^{-1}

## Q3  Magnetic dipole moment is a vector quantity directed from

• a) east to west
• b) south to north
• c) west to east
• d) north to south

• b) south to north

• a) 0
• b) -1
• c) +1
• d) ∞

• b) -1

• a) M, m/2
• b) M/2, m
• c) M, m
• d) M/2, m/2

• b) M/2, m

• a) F
• b) F/4
• c) 2F
• d) F/2

• a) F

• a) True
• b) False

• b) False

## Q8 If horizontal and vertical components of earth's magnetic field are equal, then angle of dip is will be

• (a) 30^{0}
• (b) 60^{0}
• (c) 90^{0}
• (d) 45^{0}

• (d) 45^{0}

• a) True
• d) False

• (a) True

## Q10 Dimensional formula for magnetic dipole moment is:

• a) L^{2}A^{-1}
• b) L^{2}A^{}
• c) L^{2}A^{-2}
• d) L^{1}A^{-1}

• b) L^{2}A^{}`

### ELECTRIC DIPOLE NOTES: ELECTRIC DIPOLE , DIPOLE LENGTH, ELECTRIC FIELD DUE TO ELECTRIC DIPOLE

Electric Dipole: It is a  system of equal and opposite charges separated by some  fixed distance. DIPOLE LENGTH : the distance AB = 2a is ... 