Practice Questions

Q18.In the given circuit, the equivalent resistance between the terminal A and B is ____ Ω

Q18.A potential V0 is applied across a uniform wire of resistance R. The power dissipation is P1. The wire is then cut into two equal halves and a potential of V0 is applied across the length of each half. The total power dissipation across two wires is P2. The ratio of P2 : P1 is √x : 1. The value of x is _____.

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

Q18.A capacitor has capacitance 5 µF when its parallel plates are separated by air medium of thickness d. A slab of material of dielectric constant 1. 5 having area equal to that of plates but thickness d2 is inserted between the plates. Capacitance of the capacitor in the presence of slab will be ______ µF .

Q18.Equivalent resistance between the adjacent corners of a regular n -sided polygon of uniform wire of resistance R would be : (1) (n−1)R (2) (n−1)R n2 (2n−1) (3) n2R (4) (n−1)R n−1 n

Q18.If a copper wire is stretched to increase its length by 20% . The percentage increase in resistance of the wire is _____%.

Q18.If the potential difference between B and D is zero, the value of x is n1 Ω. The value of n is ______.

Q18.Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R Assertion A : The binding energy per nucleon is practically independent of the atomic number for nuclei of mass number in the range 30 to 170. Reason R : Nuclear force is short ranged. In the light of the above statements, choose the correct answer from the options given below (1) A is false but R is true (2) Both A and R are true and R is the correct explanation of A (3) Both A and R are true but R is NOT the correct (4) A is true but R is false. explanation of A

Q18.A single current carrying loop of wire carrying current I flowing in anticlockwise direction seen from +ve z direction and lying in xy plane is shown in figure. The plot of ˆj component of magnetic field (By) at a distance a (less than radius of the coil) and on yz plane vs z coordinate looks like JEE Main 2023 (29 Jan Shift 1) JEE Main Previous Year Paper (1) (2) (3) (4)

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.A null point is found at 200 cm in potentiometer when cell in secondary circuit is shunted by 5 Ω . When a resistance of 15 Ω is used for shunting null point moves to 300 cm . The internal resistance of the cell is ______ Ω .

Q18.Speed of an electron in Bohr’s 7th orbit for Hydrogen atom is 3 . 6 × 106 m s-1. The corresponding speed of the electron in 3rd orbit, in m s-1 is : (1) 1 . 8 × 106 (2) 7 . 5 × 106 (3) 3 . 6 × 106 (4) 8 . 4 × 106

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.The resistivity ( 𝜌) of semiconductor varies with temperature. Which of the following curve represents the correct behaviour? (1) (2) (3) (4)

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.Two identical cells each of emf 1. 5 V are connected in series across a 10 Ω resistance. An ideal voltmeter connected across 10 Ω resistance reads 1. 5 V . The internal resistance of each cell is _____ Ω.

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 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.For the given circuit, in the steady state, |VB −VD| = _____ V .

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.When a resistance of 5 Ω is shunted with a moving coil galvanometer, it shows a full scale deflection for a current of 250 mA, however when 1050 Ω resistance is connected with it in series, it gives full scale deflection for 25 volt. The resistance of galvanometer is _________Ω.

Q19.A massage signal of frequency 3 kHz is used to modulate a carrier signal of frequency 1 . 5 MHz. The bandwidth of the amplitude modulated wave is (1) 6 MHz (2) 6 kHz (3) 3 MHz (4) 3 kHz

Q19.A current of 2 A flows through a wire of cross-sectional area 25. 0 mm2 . The number of free electrons in a cubic meter are 2. 0 × 1028 . The drift velocity of the electrons is _____ ×10−6 ms−1 (given, charge on electron = 1. 6 × 10−19C).

Q19.Given below are two statements: Statement I : The diamagnetic property depends on temperature. Statement II : The induced magnetic dipole moment in a diamagnetic sample is always opposite to the magnetising field. In the light of given statements, choose the correct answer from the options given below (1) Both Statement I and Statement II are False (2) Statement I is incorrect but Statement II is true (3) Statement I is correct but Statement II is false (4) Both Statement I and Statement II are true

Q19.Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R . Assertion A : Electromagnets are made of soft iron. Reason R : Soft iron has high permeability and low retentivity. In the light of above statements, choose the most appropriate answer from the options given below. (1) A is not correct but R is correct (2) A is correct but R is not correct (3) Both A and R are correct and R is the correct (4) Both A and R are correct but R is NOT the explanation of A correct explanation of A JEE Main 2023 (08 Apr Shift 2) JEE Main Previous Year Paper