Q1
mcq
1 mark
The total charge of an electric dipole is
- A. Infinity
- B. Zero
- C. +e
- D. –e
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Q2
mcq
1 mark
Identify the 'WRONG' statement regarding electrostatics of conductors.
- A. Electric field inside a charged conductor is zero
- B. There is no excess charge inside a charged conductor
- C. Electric potential is constant throughout the volume of a conductor
- D. Electric field is tangential at all points on the surface of a charged conductor
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Q3
mcq
1 mark
The magnitude of drift velocity per unit electric field is called ______
- A. mobility
- B. current density
- C. resistivity
- D. conductivity
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Q4
mcq
1 mark
Statement I: A galvanometer is converted into an ammeter by connecting a resistor of low resistance in parallel with it.
Statement II: The voltage sensitivity of a galvanometer depends on number of turns of the coil.
Pick the correct answer:
- A. Both statements I and II are correct
- B. Both statements I and II are wrong
- C. Only statement I is correct
- D. Only statement II is correct
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Q5
mcq
1 mark
A small compass needle of magnetic dipole moment 'm' is placed in uniform magnetic field 'B' at an angle $\theta$, then the magnetic potential energy of the needle is
- A. +mB sin$\theta$
- B. -mB sin$\theta$
- C. +mB cos$\theta$
- D. -mB cos$\theta$
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Q6
mcq
1 mark
The Polarity of induced emf is given by
- A. Faraday's law
- B. Lenz's law
- C. Gauss's law in magnetostatics
- D. Ampere's circuital law
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Q7
mcq
5 marks
A rectangular loop moves with a velocity $\vec{v}$ from a region of uniform magnetic field to a field-free region. The magnetic field is perpendicular to the plane of the loop. Then, in the loop
- A. Kinetic energy is induced.
- B. Electric current is induced.
- C. Electric potential is induced.
- D. Changing electric kinetic energy is induced.
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Q7
mcq
1 mark
A rectangular loop is moving out of a uniform magnetic field region to a field-free region with constant velocity $\vec{V}$ as shown in figure. Then, in the coil
- A. No emf is induced
- B. No current is induced
- C. Constant emf is induced
- D. Varying emf is induced
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Q7
mcq
A rectangular loop is moving out of a uniform magnetic field region to a field – free region with constant velocity V. Here the magnetic field direction is perpendicular to the plane of the loop. Then, in the coil
- A. No emf is induced
- B. No current is induced
- C. Constant emf is induced
- D. Varying emf is induced
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Q8
mcq
1 mark
In purely inductive ac circuit, the power factor is
- A. +1
- B. –1
- D. $\infty$
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Q9
mcq
1 mark
In which of the following sequence, does electromagnetic waves are arranged in increasing order of wavelength?
- A. X-rays, ultraviolet rays, microwaves
- B. Ultraviolet rays, X-rays, microwaves
- C. Microwaves, Ultraviolet rays, X-rays
- D. X-rays, Microwaves, Ultraviolet rays
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Q10
mcq
1 mark
A ray of light travelling from denser to rarer medium undergoes total internal reflection when
- A. angle of incidence is less than critical angle
- B. angle of incidence is greater than critical angle
- C. angle of incidence is equal to critical angle
- D. angle of incidence is zero
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Q11
mcq
1 mark
For which one of the following phase difference between two coherent light waves, the constructive interference takes place?
- A. $\pi / 2$
- B. $\pi$
- C. $2 \pi$
- D. $3\pi$
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Q12
mcq
1 mark
If Planck's constant and basic unit of electric charge are 'h' and 'e' respectively, then in photoelectric effect, the graph between stopping potential ($V_0$) and frequency ($\nu$) is a straight line with slope equal to _______.
- A. h/e
- B. e/h
- C. e
- D. h
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Q13
mcq
1 mark
de Broglie hypothesis provides an explanation for
- A. J. J. Thomson's atomic model
- B. Rutherford's nuclear model of atom
- C. Geiger-Marsden experiment
- D. Bohr's second postulate of quantization of angular momentum
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Q14
mcq
1 mark
The nuclear radius 'R' depends on mass number 'A' as
- A. $R \propto A^2$
- B. $R \propto A^{1/2}$
- C. $R \propto A^3$
- D. $R \propto A^{1/3}$
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Q15
mcq
1 mark
The List – I and List – II respectively represent materials and energy band gap $E_g$. Identify the correct match.
List – I | List – II
(i) Conductors | (p) $E_g > 3eV$
(ii) Insulators | (q) $E_g < 3eV$
(iii) Semiconductors | (r) $E_g = 0$
- A. (i) – (q); (ii) – (r); (iii) – (p)
- B. (i) – (r); (ii) – (p); (iii) – (q)
- C. (i) – (p); (ii) – (r); (iii) – (q)
- D. (i) – (r); (ii) – (q); (iii) – (p)
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Q16
short answer
1 mark
Polar molecules have permanent _______.
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Q17
short answer
1 mark
The _____ through any closed surface is zero.
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Q18
short answer
1 mark
In step-up transformer, the number of turns in secondary coil is _____ the number of turns in primary coil.
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Q19
short answer
1 mark
The intensity of light coming out of a single polaroid is _____ the incident intensity.
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Q20
short answer
1 mark
In interaction of radiation with matter, radiation behaves as if it is made up of packet of energy called ______.
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Q21
short answer
2 marks
State and explain Coulomb's law in electrostatics.
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Q22
short answer
2 marks
Graphically represent the variation of resistivity with absolute temperature for the following materials.
(i) Copper
(ii) Semi conductor
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Q23
short answer
2 marks
What is Lorentz force? Write the expression for it.
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Q24
short answer
2 marks
The current in a coil falls from 2A to 0 in time 0.1s. If an average emf of 20V is induced in this coil, then calculate its self-inductance.
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Q25
short answer
2 marks
Give any two uses of infrared waves.
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Q26
short answer
2 marks
Define power of a lens. Write its SI unit.
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Q27
short answer
2 marks
Write two advantages of reflecting telescope over refracting telescope.
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Q28
short answer
2 marks
On which factors does the conductivity of extrinsic semiconductor depend?
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Q29
short answer
3 marks
Write three properties of electric field lines.
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Q30
long answer
3 marks
Obtain an expression for effective capacitance of two capacitors connected in parallel.
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Q31
long answer
3 marks
A square coil of side 10 cm, 50 turns, carrying a current of 10A is placed in uniform magnetic field of 0.80 T in such a way that, the normal drawn to the plane of the coil makes an angle 30° with the direction of magnetic field. Find the magnitude of torque experienced by the coil.
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Q32
short answer
3 marks
Distinguish between diamagnetic and paramagnetic materials.
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Q33
long answer
3 marks
Derive the expression for motional emf induced in a straight conductor moving perpendicular to the uniform magnetic field.
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Q34
short answer
3 marks
Write three experimental observations of photoelectric effect.
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Q35
short answer
3 marks
State the three postulates of Bohr's atomic model.
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Q36
short answer
3 marks
Mention the characteristic features of nuclear force.
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Q37
long answer
5 marks
Define electrostatic potential. Obtain an expression for electrostatic potential at a point due to an isolated point charge.
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Q38
long answer
5 marks
Using Kirchhoff's laws, arrive at the balancing condition of the Wheatstone bridge.
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Q39
long answer
5 marks
Derive an expression for magnetic field at a point on the axis of a circular current loop.
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Q41
short answer
2 marks
State Huygen's principle of wavefronts.
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Q42
long answer
3 marks
Using Huygen's principle, show that the angle of incidence is equal to the angle of reflection, when a plane wavefront is reflected by a plane surface.
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Q42
long answer
5 marks
Two-point charges 2µC and 3µC are placed at the two corners A and B of an equilateral triangle ABC of side 0.2 m. Calculate the magnitude of resultant electric field at the corner C of that triangle.
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Q43
long answer
5 marks
Two identical cells either connected in series or in parallel combination give the same value of current 0.5A through an external resistor of resistance 2Ω. Find the emf and internal resistance of each cell.
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Q44
long answer
3 marks
Explain the working of a full-wave rectifier using neat circuit diagram.
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Q44
long answer
5 marks
A resistor of 100 Ω, an inductor of 200 mH and a capacitor of 100 µF are connected in series to a 220V, 50 Hz ac source. Calculate (i) impedance and (ii) current in the circuit.
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Q45
short answer
1 mark
Draw input-output waveforms of full-wave rectifier.
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Q45
long answer
5 marks
The angle of minimum deviation produced in a glass prism is 40°. Calculate the refractive index of the material of the prism, if the refracting angle of prism is 60°. Also calculate the new angle of minimum deviation when the prism is immersed in water of refractive index 1.33.
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