Practice Questions

Q18.The mass of proton, neutron and helium nucleus are respectively 1 . 0073 u, 1 . 0087 u and 4 . 0015u. The binding energy of helium nucleus is: (1) 14 . 2 MeV (2) 28 . 4 MeV (3) 56 . 8 MeV (4) 7 . 1 MeV

Q18.Two radioactive elements 𝐴 and 𝐵 initially have same number of atoms. The half life of 𝐴 is same as the average life of 𝐵. If 𝜆𝐴 and 𝜆𝐵 are decay constants of 𝐴 and 𝐵 respectively, then choose the correct relation from the given options. (1) 𝜆𝐴ln2 = 𝜆𝐵 (2) 𝜆𝐴= 𝜆𝐵 (3) 𝜆𝐴= 𝜆𝐵ln2 (4) 𝜆𝐴= 2𝜆𝐵

Q18.Consider the following radioactive decay process: 𝛼 𝛽- 𝛾 𝛼 𝛽+ 𝛾 218𝐴84 ⟶𝐴1 ⟶𝐴2 ⟶𝐴3 ⟶𝐴4 ⟶𝐴5 ⟶𝐴6 The mass number and the atomic number of A6 are given by: (1) 210 and 82 (2) 210 and 84 (3) 210 and 80 (4) 211 and 80

Q18.If each diode has a forward bias resistance of 25Ω in the below circuit, Which of the following options is correct? (1) I1 = 1 (2) I2 = 1 I2 I3 I1 I3 (3) = 2 (4) = 1 I2 I4

Q18.A student is provided with a variable voltage source V , a test resistor RT = 10Ω , two identical galvanometers G1 and G2 and two additional resistors, R1 = 10MΩ and R2 = 0. 001Ω . For conducting an experiment to verify ohm's law, the most suitable circuit is: (1) (2) (3) (4) JEE Main 2023 (06 Apr Shift 2) JEE Main Previous Year Paper

Q18. The current flowing through R2 is : (1) 3 2 A (2) 12 A (3) 1 3 A (4) 14 A

Q18.In this figure the resistance of the coil of galvanometer G is 2 Ω. The emf of the cell is 4 V. The ratio of potential difference across C1 and C2 is (1) 1 (2) 45 (3) 5 (4) 3 4 4

Q18.Name the logic gate equivalent to the diagram attached (1) NAND (2) AND (3) NOR (4) OR

Q18.A free neutron decays into a proton but a free proton does not decay into neutron. This is because (1) neutron is an uncharged particle (2) proton is a charged particle (3) neutron is a composite particle made of a proton (4) neutron has larger rest mass than proton and an electron

Q19.The electric current in a circular coil of four turns produces a magnetic induction 32 T at its centre. The coil is unwound and is rewound into a circular coil of single turn, the magnetic induction at the centre of the coil by the same current will be : (1) 8 T (2) 4 T (3) 2 T (4) 16 T

Q19.As shown in the figure, a current of 2 A flowing in an equilateral triangle of side 4√3 cm . The magnetic field at the centroid O of the triangle is : (Neglect the effect of earth’s magnetic field) (1) 4√3 × 10−4 T (2) 4√3 × 10−5 T (3) √3 × 10−4 T (4) 3√3 × 10−5 T

Q19.Match the List I with List II List I List II AIntrinsic I Fermi-level near valence band Semiconductor Fermi-level at middle of valence and conduction B n-type semiconductor II band C p-type semiconductor III Fermi-level near conduction band DMetals IVFermi-level inside conduction band Choose the correct answer from the options given below: (1) (A) → I, (B) → II, (C) → III, (D) → IV (2) (A) → II, (B) → I, (C) → III, (D) → IV (3) (A) → II, (B) → III, (C) → I, (D) → IV (4) (A) → III, (B) → I, (C) → II, (D) → IV

Q19.The magnitude of magnetic induction at mid-point O due to current arrangement as shown in figure will be . (1) μ0I (2) 0 2πa (3) μ0I (4) μ0I 4πa πa

Q19.Match List I with List II List – I List – II (Current configuration) (Magnetic field at point O ) + A I. B0 = μ0I4πr [π 2] JEE Main 2023 (25 Jan Shift 1) JEE Main Previous Year Paper B II. B0 = μ04 Ir C III. B0 = μ0I2πr [π −1] + D IV. B0 = μ0I4πr [π 1] Choose the correct answer from the option given below: (1) A-III, B-IV, C-I, D-II (2) A-I, B-III, C-IV, D-II (3) A-III, B-I, C-IV, D-II (4) A-II, B-I, C-IV, D-III

Q19.The resistance of a wire is 5 Ω. Its new resistance in ohm, if stretched to 5 times of its original length will be : JEE Main 2023 (25 Jan Shift 2) JEE Main Previous Year Paper (1) 625 (2) 125 (3) 5 (4) 25

Q19.A zener diode of power rating 1 . 6 W is to be used as voltage regulator. If the zener diode has a breakdown of 8 V and it has to regulate voltage fluctuating between 3 V and 10 V The value of resistance 𝑅𝑠 for safe operation of diode will be (1) 10 Ω (2) 12 Ω (3) 13 . 3 Ω (4) 13 Ω

Q19.Figure shows a part of an electric circuit. The potentials at points a, b and c are 30 V, 12 V and 2 V respectively. The current through the 20 Ω resistor will be, (1) 1. 0 A (2) 0. 4 A (3) 0. 6 A (4) 0. 2 A

Q19.The half-life of a radioactive nucleus is 5 years. The fraction of the original sample that would decay in 15 years is : (1) 1 (2) 1 8 4 (3) 7 (4) 3 8 4

Q20.A square loop of area 25 cm2 has a resistance of 10 Ω . The loop is placed in uniform magnetic field of magnitude 40. 0 T . The plane of loop is perpendicular to the magnetic field. The work done in pulling the loop out of the magnetic field slowly and uniformly in 1. 0 sec, will be JEE Main 2023 (29 Jan Shift 2) JEE Main Previous Year Paper (1) 2. 5 × 10−3 J (2) 1. 0 × 10−3 J (3) 1. 0 × 10−4 J (4) 5 × 10−3 J

Q20.The height of transmitting antenna is 180 m and the height of the receiving antenna is 245 m . The maximum distance between them for satisfactory communication in line of sight will be: (given R = 6400 km ) JEE Main 2023 (15 Apr Shift 1) JEE Main Previous Year Paper (1) 96 km (2) 56 km (3) 48 km (4) 104 km

Q20.Which of the following frequencies does not belong to FM broadcast. (1) 106 𝑀𝐻𝑧 (2) 64 𝑀𝐻𝑧 (3) 99 𝑀𝐻𝑧 (4) 89 𝑀𝐻𝑧

Q20.A sinusoidal carrier voltage is amplitude modulated. The resultant amplitude modulated wave has maximum and minimum amplitude of 120 V and 80 V respectively. The amplitude of each side band is : (1) 15 V (2) 10 V (3) 20 V (4) 5 V

Q20.The source of time varying magnetic field may be (A) a permanent magnet (B) an electric field changing linearly with time (C) direct current (D) a decelerating charge particle (E) an antenna fed with a digital signal Choose the correct answer from the options given below. (1) (C) and (E) only (2) (D) only (3) (A) only (4) (B) and (D) only

Q20.A long conducting wire having a current I flowing through it, is bent into a circular coil of N turns. Then it is bent into a circular coil of n turns. The magnetic field is calculated at the centre of coils in both the cases. The ratio of the magnetic field in first case to that of second case is: (1) N : n (2) n2 : N 2 (3) N 2 : n2 (4) n : N

Q20.By what percentage will the transmission range of a TV tower be affected when the height of the tower is increased by 21%? (1) 15% (2) 12% (3) 10% (4) 14%