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International Physics Olympiad Qualifier – Grade – 12

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--------------------------------------------------------------------------------------------------------------- Max Marks: 60 Test ID: 13111 Time Allotted : 40 Mins --------------------------------------------------------------------------------------------------------------- Instructions:

• Each question has four choices (A), (B), (C) and (D) out of which ONLY ONE is correct.

• Each question carries 2 Marks. There is no negative marking

1. A voltmeter of resistance 1000 is connected across a resistance of 500 in the given circuit. What will be the reading of voltmeter?

A. 1 V B. 2 V C. 6 V D. 4 V

2. A beam contains 2 108 doubly charged positive ions per cubic centimeter, all of which are moving with a speed of 105 m/s. The current density is

A. 6.4 A/m2 B. 3.2 A/m2 C. 1.6 A/m2 D. None of these

3. In the circuit shown, the reading of ammeter when switch S is open and when switch

S is closed respectively are

A. 3 A and 4 A

B. 4 A and 5 A

C. 5 A and 6 A

D. 6 A and 7 A

4. In the circuit as shown in figure the

|Grade: 12 | |International Physics Olympiad Qualifier| | Set: 2|

V

500 500

10 V

A 3

2

2

S

20V

20 10 10 25V 0.5A

R

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A. Resistance R = 46 B. Current through 20 resistance is 0.1 A C. Potential difference across the middle resistance is 2 V D. All option are correct

5. A convex mirror of focal length f forms an image which is n

1 times the object. The

distance of the object from the mirror is

A. fn )1(

B. f

n

n

1

C. f

n

n

1

D. fn )1(

6. A diminished virtual image can be formed only in

A. Plane mirror

B. A concave mirror

C. A convex mirror

D. Concave-parabolic mirror

7. Which of the following could not produce a virtual image?

A. Plane mirror

B. Convex mirror

C. Concave mirror

D. All the above can produce a virtual image

8. An object cm5 tall is placed m1 from a concave spherical mirror which has a radius of

curvature of cm20 The size of the image is

A. cm11.0

B. cm50.0

C. cm55.0 D. cm60.0

9. The similarity between the sound waves and light waves is

A. Both are electromagnetic waves

B. Both are longitudinal waves



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C. Both have the same speed in a medium

D. They can produce interference

10. The ratio of intensities of two waves is 9 : 1. They are producing interference. The

ratio of maximum and minimum intensities will be

A. 10 : 8

B. 9 : 1

C. 4 : 1

D. 2 : 1

11. A wave can transmit ...... from one place to another

A. Energy

B. Amplitude

C. Wavelength

D. Matter

12. If the ratio of intensities of two waves is 1 : 25, then the ratio of their amplitudes will

be

A. 1 : 25

B. 5 : 1

C. 26 : 24

D. 1 : 5

13. Two parallel long wires carry currents i1 and i2 with 21 ii . When the currents are in

the same direction, the magnetic field midway between the wires is 10 T. When the

direction of i2 is reversed, it becomes 40 T. the ratio 21 / ii is

A. 3 : 4 B. 11 : 7 C. 7 : 11 D. 5 : 3

14. Two circular coils X and Y, having equal number of turns, carry equal currents in the

same sense and subtend same solid angle at point O. If the smaller coil, X is midway

between O and Y, then if we represent the magnetic induction due to bigger coil Y at

O as BY and that due to smaller coil X at O as BX , then

A.

1X

Y

B

B



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B.

2X

Y

B

B

C. 2

1

X

Y

B

B

D. 4

1

X

Y

B

B

15. A fixed horizontal wire carries a current of 200 A. Another wire having a mass per

unit length mkg /10 2 is placed below the first wire at a distance of 2 cm and parallel

to it. How much current must be passed through the second wire if it floats in air without any support? What should be the direction of current in it

A. 25A (direction of current is same to first wire) B. 25A (direction of current is opposite to first wire) C. 49 A (direction of current is same to first wire) D. 49 A (direction of current is opposite to first wire)

16. Find magnetic field at O

A. r

i

24

5 0

B. r

i

24

0

C. r

i

24

11 0

D. Zero 17. A magnet is suspended horizontally in the earth's magnetic field. When it is

displaced and then released it oscillates in a horizontal plane with a period T. If a

place of wood of the same moment of inertia (about the axis of rotation) as the

magnet is attached to the magnet what would the new period of oscillation of the

system become

A. 3/T

B. 2/T

C. 2

T

D. 2T 18. Two short magnets of magnetic moment 1000 2Am are placed as shown at the corn

ers of a square of side 10 cm. The net magnetic induction at P is

S N

BH

2r

r

d/2

O

Y

d

X

r

r

r

i

O



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A. 0.1 T B. 0.2 T C. 0.3 T D. 0.4 T

19. For characteristic X-ray of some material

A. )()()( KEKEKE

B. )()()( MELEKE

C. )()()( KKK

D. )()()( KLM

20. The maximum velocity of electrons emitted from a metal surface is V. When

frequency of light falling on it is f. The maximum velocity when frequency becomes

4f is

A. 2 V B. > 2 V C. < 2 V D. Between 2 V and 4 V

21. If the potential difference between the anode and cathode of the X-ray tube is

increases

A. The peaks at R and S would move to shorter wavelength B. The peaks at R and S would remain at the same wavelength C. The cut off wavelength at P would decrease D. B and C both are correct

22. The collector plate in an experiment on photoelectric effect is kept vertically above

the emitter plate. Light source is put on and a saturation photo current is recorded. An electric field is switched on which has a vertically downward direction

A. The photo current will increase B. The kinetic energy of the electrons will increase C. The stopping potential will decrease D. The threshold wavelength will increase

P S N

S N

I R

P

S



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23. If the series limit of Lymen series for Hydrogen atom is equal to the series limit of

Balmer series for a hydrogen like atom, then atomic number o this hydrogen like

atom will be

A. 1 B. 2 C. 3 D. 4

24. Which sample contains greater number of nuclei :

5.00- Ci sample of 240Pu (half-life 6560y) or a 4.45-Ci sample of 243Am (half-life 7370 y)

A. 240Pu B. 243Am C. Equal in both D. None of these

25. The fission of 235U can be triggered by the absorption of a slow neutrons by a nucleus.

Similarly a slow proton can also be used. This statement is

A. Correct B. Wrong C. Information is insufficient D. None of these

26. The radioactivity of a given sample of whisky due to tritium (half life 12.3 years) was

found to be only 3% of that measured in a recently purchased bottle marked "7 years old". The sample must have been prepared about

A. 220 years back B. 300 years back C. 400 years back D. 70 years back

27. The following diagram indicates the energy levels of a certain atom when the system

moves from 4E level to E. A photon of wavelength 1 is emitted. The wavelength of

photon produced during it's transition from E3

7 level to E is 2. The ratio

2

1

will be

A. 4

9

B. 9

4

4 E

E



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C. 2

3

D. 3

7

28. Pure sodium (Na) is a good conductor of electricity because the 3s and 3p atomic

bands overlap to form a partially filled conduction band. By contrast the ionic

sodium chloride (NaCl) crystal is A. Insulator B. Conductor C. Semiconductor D. None of these

29. Would there be any advantage to adding n-type or p-type impurities to copper

A. Yes B. No C. May be D. Information is insufficient

30. Which of the following elements is used for creating p-type semiconductors from a

silicon lattice? A. Antimony B. Arsenic C. Phosphorus D. Gallium


grade: 12 | |international physics ... - olympiads.org · international physics olympiad qualifier...

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