Practice Questions

Q11.Wheatstone bridge principle is used to measure the specific resistance 𝑆1 of given wire, having length 𝐿, radius 𝜋𝑟2 𝑟. If X is the resistance of wire, then specific resistance is : 𝑆1 = 𝑋 𝐿. If the length of the wire gets doubled then the value of specific resistance will be : 𝑆1 (1) (2) 2 S1 4 (3) 𝑆1 (4) 𝑆1 2

Q11.The number of electrons flowing per second in the filament of a 110 W bulb operating at 220 V is : ( Given e = 1.6 × 10−19C) (1) 6.25 × 1017 (2) 1.25 × 1019 (3) 6.25 × 1018 (4) 31.25 × 1017 JEE Main 2024 (06 Apr Shift 2) JEE Main Previous Year Paper

Q11.Ques: σ is the uniform surface charge density of a thin spherical shell of radius R. The electric field at any point on the surface of the spherical shell is : (1) σ/ϵoR (2) σ/ϵo (3) σ/4ϵo (4) σ/2ϵo

Q11.When a potential difference 𝑉 is applied across a wire of resistance 𝑅, it dissipates energy at a rate 𝑊. If the wire is cut into two halves and these halves are connected mutually parallel across the same supply, the energy dissipation rate will become: 1 1 (1) W (2) W 4 2 (3) 2 W (4) 4 W JEE Main 2024 (30 Jan Shift 2) JEE Main Previous Year Paper

Q11. The heat absorbed by a system in going through the given cyclic process is : JEE Main 2024 (05 Apr Shift 1) JEE Main Previous Year Paper (1) 19.6 J (2) 61.6 J (3) 616 J (4) 431.2 J

Q11.A wire of resistance R and length L is cut into 5 equal parts. If these parts are joined parallely, then resultant resistance will be : (1) R (2) R 25 5 (3) 25R (4) 5R

Q11.A potential divider circuit is shown in figure. The output voltage V0 is (1) 4 V (2) 2 mV (3) 0. 5 V (4) 12 mV JEE Main 2024 (30 Jan Shift 1) JEE Main Previous Year Paper

Q11.A galvanometer 𝐺 of 2𝛺 resistance is connected in the given circuit. The ratio of charge stored in 𝐶1 and 𝐶2 is: 2 3 (1) (2) 3 2 1 (3) 1 (4) 2

Q11.A charge q is placed at the center of one of the surface of a cube. The flux linked with the cube is: (1) q (2) q 2ϵ0 8ϵ0 (3) Zero (4) q 4ϵ0

Q11.By what percentage will the illumination of the lamp decrease if the current drops by 20%? (1) 46% (2) 26% (3) 36% (4) 56%

Q12.A wire of length 10 cm and radius √7 × 10−4 m connected across the right gap of a meter bridge. When a resistance of 4. 5 Ω is connected on the left gap by using a resistance box, the balance length is found to be at 60 cm from the left end. If the resistivity of the wire is R × 10−7 Ω m , then value of R is : (1) 63 (2) 70 (3) 66 (4) 35

Q12.An electric toaster has resistance of 60 Ω at room temperature (27 °C). The toaster is connected to a 220 V supply. If the current flowing through it reaches 2. 75 A, the temperature attained by toaster is around: (if α = 2 × 10−4 ∘C−1 ) (1) 694°C (2) 1235°C (3) 1694°C (4) 1667°C

Q12.Water boils in an electric kettle in 20 minutes after being switched on. Using the same main supply, the length of the heating element should be _____ to _____ times of its initial length if the water is to be boiled in 15 minutes. (1) decreased, 3/4 (2) increased, 4/3 (3) decreased, 4/3 (4) increased, 3/4

Q12.The fundamental frequency of a closed organ pipe is equal to the first overtone frequency of an open organ pipe. If length of the open pipe is 60 cm, the length of the closed pipe will be : (1) 60 cm (2) 45 cm (3) 30 cm (4) 15 cm

Q12.The ratio of heat dissipated per second through the resistance 5Ω and 10Ω in the circuit given below is : (1) 1 : 2 (2) 2 : 1 (3) 4 : 1 (4) 1 : 1 −

Q12.A square loop of side 15 cm being moved towards right at a constant speed of 2 cm/s as shown in figure. The front edge enters the 50 cm wide magnetic field at t = 0 . The value of induced emf in the loop at t = 10 s will JEE Main 2024 (09 Apr Shift 2) JEE Main Previous Year Paper be : (1) 0.3mV (2) zero (3) 4.5mV (4) 3mV

Q12.In the given circuit, the current in resistance R3 is: (1) 1 A (2) 1. 5 A (3) 2 A (4) 2. 5 A

Q12.A capacitor of capacitance 100 μF is charged to a potential of 12 V and connected to a 6. 4 mH inductor to produce oscillations. The maximum current in the circuit would be : (1) 3. 2 A (2) 1. 5 A (3) 2. 0 A (4) 1. 2 A

Q12.An infinitely long positively charged straight thread has a linear charge density λCm−1 . An electron revolves along a circular path having axis along the length of the wire. The graph that correctly represents the variation JEE Main 2024 (04 Apr Shift 1) JEE Main Previous Year Paper of the kinetic energy of electron as a function of radius of circular path from the wire is : (1) (2) (3) (4)

Q12.In the given circuit, the terminal potential difference of the cell is : (1) 2 V (2) 3 V (3) 4 V (4) 1.5 V

Q12.A current of 200 μA deflects the coil of a moving coil galvanometer through 60°. The current to cause 𝜋 deflection through radian is 10 (1) 30 μA (2) 120 μA (3) 60 μA (4) 180 μA

Q12.A galvanmeter has a coil of resistance 200Ω with a full scale deflection at 20μA. The value of resistance to be added to use it as an ammeter of range (0 −20)mA is ; (1) 0.40Ω (2) 0.20Ω (3) 0.50Ω (4) 0.10Ω

Q12.An electric bulb rated 50 W −200 V is connected across a 100 V supply. The power dissipation of the bulb is: (1) 25 W (2) 12.5 W (3) 50 W (4) 100 W

Q12.In a metre-bridge when a resistance in the left gap is 2 Ω and unknown resistance in the right gap, the balance length is found to be 40 cm . On shunting the unknown resistance with 2 Ω, the balance length changes by: (1) 22 . 5 cm (2) 20 cm (3) 62 . 5 cm (4) 65 cm JEE Main 2024 (01 Feb Shift 2) JEE Main Previous Year Paper

Q12.An alternating voltage 𝑉( 𝑡) = 220sin100𝜋t volt is applied to a purely resistive load of 50 𝛺. The time taken for the current to rise from half of the peak value to the peak value is: (1) 5 ms (2) 3 . 3 ms (3) 7 . 2 ms (4) 2 . 2 ms