ISC Physics 2019 Question Paper with Answers
All 40 questions of the ISC Physics 2019 Question Paper, in printed order. Open a question to read it in full and see its answer.
- Q1(A)(i) A closed surface in vacuum encloses charges $-q$ and $+3q$. The total electric flux emerging out of the surface is: 1 mark · MCQ
- Q1(A)(ii) What is the angle of dip at a place where the horizontal component ($B_H$) and vertical component ($B_V$) of earth’s magnetic… 1 mark · MCQ
- Q1(A)(iii) A beam of light is incident at the polarizing angle of $35^\circ$ on a certain glass plate. The refractive index of the glass… 1 mark · MCQ
- Q1(A)(iv) In a gamma ray emission from nucleus: 1 mark · MCQ
- Q1(A)(v) The energy associated with light of which of the following colours is minimum: 1 mark · MCQ
- Q1(B)(i) Define equipotential surface. 1 mark · Short answer
- Q1(B)(ii) Calculate the net emf across A and B shown in Figure 1 below: 1 mark · Numerical
- Q1(B)(iii) Why are the pole pieces of a horseshoe magnet in a moving coil galvanometer made cylindrical in shape? 1 mark · Short answer
- Q1(B)(iv) What is the value of power factor for a pure resistor connected to an alternating current source? 1 mark · Short answer
- Q1(B)(v) What should be the path difference between two waves reaching a point for obtaining constructive interference in Young’s Double… 1 mark · Short answer
- Q1(B)(vi) Define critical angle for a given medium. 1 mark · Short answer
- Q1(B)(vii) Name the series in the atomic spectra of the hydrogen atom that falls in the ultra violet region. 1 mark · One word
- Q2 In a potentiometer experiment, the balancing length with a resistance of $2\\ \Omega$ is found to be $100\text{ cm}$, while that… 2 marks · Numerical
- Q3 A rectangular loop of area $5\text{ m}^2$, has $50$ turns and carries a current of $1\text{ A}$. It is held in a uniform magnetic… 2 marks · Numerical
- Q4(a) An electric current $I$ flows through an infinitely long conductor as shown in Figure 2(a) below. Write an expression and… 2 marks · Short answer
- Q4(b) An electric current $I$ flows through a circular loop as shown in Figure 2(b) below. Write an expression and direction for the… 2 marks · Short answer
- Q5 A transformer is used to step up an alternating emf of $200\text{ V}$ to $440\text{ V}$. If the primary coil has $1000$ turns… 2 marks · Numerical
- Q6 State any two properties of microwaves. 2 marks · Short answer
- Q7 Write any one use for each of the following mirrors: Convex Concave 2 marks · Short answer
- Q8 The deviation produced for violet, yellow and red lights for crown glass are $3\cdot75^\circ$, $3\cdot25^\circ$ and… 2 marks · Numerical
- Q9 What is meant by mass defect? What conclusion is drawn from Rutherford’s scattering experiment of $\alpha$-particles? 2 marks · Short answer
- Q10 Define the following with reference to photoelectric effect: Threshold frequency ($f_0$) Stopping potential ($V_s$) 2 marks · Short answer
- Q11(a) The half-life of radium is $1550$ years. Calculate its disintegration constant ($\lambda$). 2 marks · Numerical
- Q11(b) Copy and complete the following table for a radioactive element whose half-life is 10 minutes. Assume that you have 30g of this… 2 marks · Short answer
- Q12 Define frequency modulation and state any one advantage of frequency modulation (FM) over amplitude modulation (AM). 2 marks · Short answer
- Q13 Obtain an expression for electric potential ‘V’ at a point in an end-on position i.e. axial position of an electric dipole. 3 marks · Derivation
- Q14 Three capacitors of capacitance $C_1 = 3\\ \mu\text{F}$, $C_2 = 6\\ \mu\text{F}$ and $C_3 = 10\\ \mu\text{F}$, are connected to a… 3 marks · Numerical
- Q15(a) Obtain the balancing condition for the Wheatstone bridge arrangement as shown in Figure 4 below: 3 marks · Derivation
- Q15(b) Draw a labelled circuit diagram of a potentiometer to measure the internal resistance ‘r’ of a cell. Write the working formula… 3 marks · Drawing
- Q16(a) A ray of light is incident on a prism whose refractive index is $1\cdot52$ at an angle of $40^\circ$. If the angle of emergence… 3 marks · Numerical
- Q16(b) Calculate the focal length of a convex lens whose radii of curvature of two surfaces is $10\text{ cm}$ and $15\text{ cm}$… 3 marks · Numerical
- Q17 Derive the law of reflection using Huygen’s Wave Theory. 3 marks · Derivation
- Q18 State any two Bohr’s postulates and write the energy value of the ground state of the hydrogen atom. 3 marks · Short answer
- Q19 With reference to semi-conductors answer the following: What is the change in the resistance of the semi-conductor with increase… 3 marks · Short answer
- Q20(a) An alternating emf of $200\text{ V}$, $50\text{ Hz}$ is applied to an L-R circuit, having a resistance $R$ of $10\\ \Omega$ and… 5 marks · Numerical
- Q20(b) An a.c. source of emf $\varepsilon = 200 \sin \omega t$ is connected to a resistor of $50\\ \Omega$. Calculate: (1) Average… 5 marks · Short answer
- Q21(a) Draw a neat labelled ray diagram showing the formation of an image at the least distance of distinct vision D by a simple… 5 marks · Derivation
- Q21(b) Draw a neat labelled diagram of Young’s Double Slit experiment. Show that $\beta = \frac{\lambda D}{d}$, where the terms have… 5 marks · Derivation
- Q22(a) Draw a labelled circuit diagram of a half wave rectifier and give its output waveform. Draw a symbol for NOR gate and write its… 5 marks · Drawing
- Q22(b) Draw a neat circuit diagram to study the input and output characteristics of a common emitter transistor. Draw the symbol for AND… 5 marks · Drawing