Practice Questions

Q10.A particle executes SHM of amplitude 𝐴. The distance from the mean position when its kinetic energy becomes equal to its potential energy is: (1) 1 (2) 2𝐴 √2𝐴 (3) √2𝐴 (4) 12𝐴

Q10.A body cools from 60°C to 40°C in 6 minutes. If, temperature of surroundings is 10°C . Then, after the next 6 minutes, its temperature will be ______ °C.

Q10.The distance between two plates of a capacitor is 𝑑 and its capacitance is 𝐶1, when air is the medium between 2𝑑 the plates. If a metal sheet of thickness and of the same area as plate is introduced between the plates, the 3 𝐶2 capacitance of the capacitor becomes 𝐶2 . The ratio is 𝐶1 (1) 3 : 1 (2) 2 : 1 (3) 4 : 1 (4) 1 : 1

Q10.Glycerin of density 1. 25 × 103 kg m–3 is flowing through the conical section of pipe. The area of cross- section of the pipe at its ends are 10 cm2 and 5 cm2 and pressure drop across its length is 3 N m–2 . The rate of flow of glycerine through the pipe is x × 10–5 m3 s–1 . The value of x is _____.

Q10.As shown in the figure, in an experiment to determine Young's modulus of a wire, the extension-load curve is plotted. The curve is a straight line passing through the origin and makes an angle of 45° with the load axis. The length of wire is 62. 8 cm and its diameter is 4 mm. The Young's modulus is found to be x × 104 N m−2 The value of x is _______.

Q10.In a linear Simple Harmonic Motion (SHM) (A) Restoring force is directly proportional to the displacement. (B) The acceleration and displacement are opposite in direction. (C) The velocity is maximum at mean position. (D) The acceleration is minimum at extreme points. Choose the correct answer from the options given below: (1) (C) and (D) only (2) (A), (C) and (D) only (3) (A), (B) and (C) only (4) (A), (B) and (D) only

Q10.The elastic potential energy stored in a steel wire of length 20 m stretched through 2 cm is 80 J. The cross sectional area of the wire is _____ mm2. (Given, Y = 2. 0 × 1011 N m–2 )

Q10.Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R Assertion (A) : Steel is used in the construction of buildings and bridges. Reason (R) : Steel is more elastic and its elastic limit is high. In the light of above statements, choose the most appropriate answer from the options given below (1) Both A and R are correct and R is the correct (2) Both A and R are correct but R is NOT the explanation of A correct explanation of A (3) A is correct but R is not correct (4) A is not correct but R is correct

Q10.A particle executes S.H.M. of amplitude 𝐴 along 𝑥-axis. At 𝑡= 0, the position of the particle is 𝑥= and it 2 moves along positive 𝑥-axis. The displacement of particle in time 𝑡 is 𝑥= 𝐴 sin𝜔𝑡 + 𝛿, then the value 𝛿 will be (1) 𝜋 (2) 𝜋 2 6 𝜋 𝜋 (3) (4) 3 4

Q10.A steel rod of length 1 m and cross-sectional area 10−4 m2 is heated from 0°C to 200°C without being allowed to extend or bend. The compressive tension produced in the rod is _____ ×104 N . (Given Young's modulus of steel = 2 × 1011 N m−2 , coefficient of linear expansion = 10−5 K−1 )

Q10.A spherical drop of liquid splits into 1000 identical spherical drops. If ui is the surface energy of the original = ( 10x ). Then drop and uf is the total surface energy of the resulting drops, the (ignoring evaporation), ufui value of x is ______:

Q10.The pressure ( 𝑃) and temperature ( 𝑇) relationship of an ideal gas obeys the equation 𝑃𝑇2 = constant. The volume expansion coefficient of the gas will be : 3 (1) 3𝑇2 (2) 𝑇2 3 3 (3) (4) 𝑇3 𝑇

Q10.The electric field in an electromagnetic wave is given as →𝐸= 20sin𝜔𝑡- 𝑥 →jN C-1, where 𝜔 and 𝑐 are angular frequency and velocity of electromagnetic wave 𝑐 respectively. The energy contained in a volume of 5 × 10-4 m3 will be (Given 𝜀0 = 8 . 85 × 10-12C2 N-1 m-2) (1) 88 . 5 × 10-13 J (2) 17 . 7 × 10-13 J (3) 28 . 5 × 10-13 J (4) 8 . 85 × 10-13 J

Q10.The Young's modulus of a steel wire of length 6 m and cross-sectional area 3 mm2 , is 2 × 1111 N/m2 . The wire is suspended from its support on a given planet. A block of mass 4 kg is attached to the free end of the JEE Main 2023 (01 Feb Shift 2) JEE Main Previous Year Paper wire. The acceleration due to gravity on the planet is 1 of its value on the earth. The elongation of wire is 4 (Take g on the earth = 10 m/s2 ): (1) 1 cm (2) 1 mm (3) 0. 1 mm (4) 0. 1 cm

Q10.Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R Assertion A: When you squeeze one end of a tube to get toothpaste out from the other end, Pascal’s principle is observed. Reason R: A change in the pressure applied to an enclosed incompressible fluid is transmitted undiminished to every portion of the fluid and to the walls of its container. In the light of the above statements, choose the most appropriate answer from the options given below. (1) Both A and R are correct but R is NOT the (2) A is not correct but R is correct correct explanation of A (3) A is correct but R is not correct (4) Both A and R is correct and R is the correct explanation of A

Q10.A water heater of power 2000 W is used to heat water. The specific heat capacity of water is 4200 J kg−1 K−1 . The efficiency of heater is 70%. Time required to heat 2 kg of water from 10°C to 60°C is _____ s . (Assume that the specific heat capacity of water remains constant over the temperature range of the water).

Q10.An aluminium rod with Young’s modulus Y = 7. 0 × 1010 N m−2 undergoes elastic strain of 0. 04%. The energy per unit volume stored in the rod in SI unit JEE Main 2023 (08 Apr Shift 1) JEE Main Previous Year Paper (1) 2800 (2) 11200 (3) 5600 (4) 8400

Q10.The surface tension of soap solution is 3. 5 × 10−2 N m−1 . The amount of work done required to increase the radius of soap bubble from 10 cm to 20 cm is _____ ×10−4 J . (take π = 227 )

Q11.Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R. Assertion A : Efficiency of a reversible heat engine will be highest at –273 °C temperature of cold reservoir. Reason R : The efficiency of Carnot’s engine depends not only on temperature of cold reservoir but it depends on the temperature of hot reservoir too and is given as η = (1 −T2T1 ) In the light of the above statements, choose the correct answer from the options given below : (1) A is true but R is false (2) Both A and R are true but R is NOT the correct explanation of A (3) A is false but R is true (4) Both A and R are true and R is the correct explanation of A

Q11.As shown in the figure, a network of resistors is connected to a battery of 24 V with an internal resistance of 3 𝛺. The currents through the resistors 𝑅4 and 𝑅5 are 𝐼4 and 𝐼5 respectively. The values of 𝐼4 and 𝐼5 are: 8 2 24 6 (1) 𝐼4 = 5 A and I5 = 5 A (2) 𝐼4 = 5 A and 𝐼5 = 5 A (3) 𝐼4 = 6 A and 𝐼5 = 24 A (4) 𝐼4 = 2 A and 𝐼5 = 8 A 5 5 5 5

Q11. A 10 𝜇C charge is divided into two parts and placed at 1 cm distance so that the repulsive force between them is maximum. The charges of the two parts are: (1) 7𝜇C, 3𝜇C (2) 8𝜇C, 2𝜇C (3) 5𝜇C, 5𝜇C (4) 9𝜇C, 1𝜇C

Q11.A metal block of base area 0. 20 m2 is placed on a table, as shown in figure. A liquid film of thickness 0. 25 mm is inserted between the block and the table. The block is pushed by a horizontal force of 0. 1 N and moves with a constant speed. If the viscosity of the liquid is 5. 0 × 10–3 Pl, the speed of block is ______ ×10−3 m s−1 .

Q11.An air bubble of volume 1 cm3 rises from the bottom of a lake 40 m deep to the surface at a temperature of 12°C. The atmospheric pressure is 1 × 105 Pa, the density of water is 1000 kg m−3 and g = 10 m s−2. There is no difference of the temperature of water at the depth of 40 m and on the surface. The volume of air bubble when it reaches the surface will be (1) 2 cm3 (2) 3 cm3 (3) 4 cm3 (4) 5 cm3

Q11.Let 𝜎 be the uniform surface charge density of two infinite thin plane sheets shown in figure. Then the electric fields in three different region 𝐸𝐼 , 𝐸𝐼𝐼 and 𝐸𝐼𝐼𝐼 (1) → 𝐸𝐼= 2𝜎 ^𝑛, →𝐸𝐼𝐼= 0, →𝐸𝐼𝐼𝐼= 2𝜎 ^𝑛 (2) →𝐸𝐼= 0, →𝐸𝐼𝐼= 𝜎 ^𝑛, →𝐸𝐼𝐼𝐼= 0 ∈0 ∈0 ∈0 → 𝜎 → → 𝜎 → -𝜎 → → 𝜎 (3) ^𝑛 𝐸𝐼= ^𝑛, 𝐸𝐼𝐼= 0, 𝐸𝐼𝐼𝐼= 𝐸𝐼= 2 ∈0 ^𝑛, 𝐸𝐼𝐼= 0, 𝐸𝐼𝐼𝐼= 2 ∈0 ^𝑛 (4) ∈0 ∈0

Q11.Which of the following correctly represents the variation of electric potential ( 𝑉) of a charged spherical conductor of radius ( 𝑅) with radial distance ( 𝑟) from the centre? (1) (2) (3) (4)