ISC Physics 2023 Specimen Paper with Answers
All 39 questions of the ISC Physics 2023 Specimen Paper, in printed order. Open a question to read it in full and see its answer.
- Q1(A)(i) The surface charge density of a large conducting sheet is $17\cdot7 \times 10^{-6}\text{ C}\cdot\text{m}^{-2}$. The electric… 1 mark · MCQ
- Q1(A)(ii) If $R_1$ and $R_2$ are filament resistances of a $100\text{ W}$ bulb and a $50\text{ W}$ bulb respectively, designed to operate… 1 mark · MCQ
- Q1(A)(iii) Magnetic flux density ($B$) of the magnetic field at a point on the axis of a long straight solenoid is given by: 1 mark · MCQ
- Q1(A)(iv) Two thin lenses having optical powers of $-8\text{ D}$ and $+12\text{ D}$ are placed in contact with each other. The focal length… 1 mark · MCQ
- Q1(A)(v) Cylindrical wavefronts are produced by: 1 mark · MCQ
- Q1(A)(vi) The graph of de-Broglie wavelength ($\lambda$) of a moving electron versus its velocity ($v$) is: 1 mark · MCQ
- Q1(A)(vii) ‘n’ type semiconductor is that which has 1 mark · MCQ
- Q1(B)(i) In an electric dipole, what is the locus of a point having zero potential? 1 mark · Short answer
- Q1(B)(ii) Name the conservation principle implied in Kirchhoff’s Junction law for electric circuits. 1 mark · Short answer
- Q1(B)(iii) Give any one reason why efficiency of a transformer is always less than 1. 1 mark · Short answer
- Q1(B)(iv) Give an example of coherent sources of light. 1 mark · Short answer
- Q1(B)(v) In Young’s double slit experiment, what is the path difference between the two light waves forming 5th bright fringe on the… 1 mark · Short answer
- Q1(B)(vi) State the function of a moderator in a nuclear reactor. 1 mark · Short answer
- Q1(B)(vii) In semiconductors, what is meant by “doping”? 1 mark · Short answer
- Q2(i) You are provided with many identical capacitors each of capacitance $100\\,\mu\text{F}$. How will you connect a minimum number of… 2 marks · Drawing
- Q2(ii) Three point charges of $50\text{ nC}$ each are kept at the vertices of an equilateral triangle having each side $= 3\text{ m}$… 2 marks · Numerical
- Q3 With reference to free electron theory of conductors, define: Drift velocity State any one use of a potentiometer. 2 marks · Short answer
- Q4 Explain why a blue coloured spark is often seen in a switch when a circuit containing an electric iron/geyser is switched off. 2 marks · Short answer
- Q5(i) Two long straight wires A and B are kept parallel to each other, $5\text{ cm}$ apart, in vacuum. They carry currents of… 2 marks · Numerical
- Q5(ii) An electron moving with a velocity of $8 \times 10^6\text{ m/s}$ enters a uniform and transverse magnetic field of… 2 marks · Numerical
- Q6 Name the electromagnetic radiation: used for viewing through haze and fog. which has the wavelength of $0\cdot1\text{ nm}$. 2 marks · Short answer
- Q7 Draw a neat and labelled ray diagram to show the formation of a primary rainbow. 2 marks · Drawing
- Q8 With reference to a semiconductor diode, explain the terms: Depletion region Potential barrier or barrier p.d. 2 marks · Short answer
- Q9 Obtain an expression for intensity of electric field at a point in end on position i.e. on an axial line of an electric dipole. 3 marks · Derivation
- Q10(i) In a meter bridge circuit, resistance in the left gap is $4\\,\Omega$ and an unknown resistance $R$ is in the right-hand gap as… 3 marks · Numerical
- Q10(ii) A circuit is used to determine the internal resistance and the emf of a cell. It consists of the cell, a variable resistor, an… 3 marks · Numerical
- Q11 Obtain an expression for magnetic flux density $B$ at the centre of a current carrying circular coil. 3 marks · Derivation
- Q12 Using Huygen’s wave theory, prove Snell’s law of refraction of light. 3 marks · Derivation
- Q13(i) Obtain Prism formula i.e. prove that $n = \frac{\sin\left(\frac{A + \delta_m}{2}\right)}{\sin\left(\frac{A}{2}\right)}$ Where the… 3 marks · Derivation
- Q13(ii) Derive Lens Maker’s formula. 3 marks · Derivation
- Q14 Calculate the angular width of the central maxima obtained in Fraunhofer single slit diffraction experiment, when a monochromatic… 3 marks · Numerical
- Q15 With reference to photoelectric effect, plot a labelled graph of stopping potential ($V_s$) versus frequency ($f$) of the… 3 marks · Drawing
- Q16 State any two differences between Nuclear fusion and Nuclear fission. What is the essential difference between the working of a… 3 marks · Short answer
- Q17 What is meant by reverse biasing of a semiconductor diode? Draw a labelled characteristic curve i.e. I - V graph for a… 3 marks · Drawing
- Q18(i) An $80\\,\Omega$ resistor, a $1\cdot0\text{ H}$ inductor and a $40\\,\mu\text{F}$ capacitor are connected in series to an a.c… 5 marks · Numerical
- Q18(ii) Figure 4 below shows two thick metallic rails CD and GH kept parallel to each other $0\cdot8\text{ m}$ apart. They are joined to… 5 marks · Numerical
- Q19(i) Using Bohr’s theory of hydrogen atom, obtain an expression for the radius of the $n^{\text{th}}$ orbit of an electron in an atom… 5 marks · Long answer
- Q19(ii) State the postulate of Bohr’s theory regarding: (1) Quantisation of angular momentum of an electron. (2) Emission of energy by an… 5 marks · Short answer
- Q20 Optical instruments are of great utility. They help us in studying very tiny objects as well as very large heavenly bodies… 5 marks · Case based