Practice Questions

Q9. Two different adiabatic paths for the same gas intersect two isothermal curves as shown in P-V diagram. The relation between the ratio Va and the ratio Vb is: Vd Vc (1) Va ≠Vb (2) Va = Vb Vd Vc Vd Vc (3) Va Vb −1 (4) Va Vb 2 = = Vd ( Vc ) Vd ( Vc )

Q9. The pressure and volume of an ideal gas are related as 𝑃𝑉 32 = 𝐾 (Constant). The work done when the gas is taken from state 𝐴𝑃1, 𝑉1, 𝑇1 to state 𝐵𝑃2, 𝑉2, 𝑇2 is : (1) 2 ( 𝑃1𝑉1 - 𝑃2𝑉2 ) (2) 2 ( 𝑃2𝑉2 - 𝑃1𝑉1 ) (3) 2√𝑃1𝑉1 −√𝑃2𝑉2 (4) 2𝑃2√𝑉2 −𝑃1√𝑉1

Q9. The average kinetic energy of a monatomic molecule is 0. 414 eV at temperature: JEE Main 2024 (27 Jan Shift 1) JEE Main Previous Year Paper (Use KB = 1. 38 × 10−23 J mol−1 K−1 ) (1) 3000 K (2) 3200 K (3) 1600 K (4) 1500 K

Q9. Two thermodynamical process are shown in the figure. The molar heat capacity for process A and B are CA and CB . The molar heat capacity at constant pressure and constant volume are represented by CP and CV , respectively. Choose the correct statement. (1) CP > CB > CV (2) CA = 0 and CB = ∞ (3) CP > CV > CA = CB (4) CA > CP > CV

Q9. The speed of sound in oxygen at S.T.P. will be approximately: (Given, 𝑅= 8 . 3 J K-1, 𝛾= 1 . 4) (1) 310 m s-1 (2) 333 m s-1 (3) 341 m s-1 (4) 325 m s-1

Q9. If three moles of monoatomic gas 𝛾= 5 is mixed with two moles of a diatomic gas 𝛾= 7 the value of adiabatic 3 5, exponent 𝛾 for the mixture is: (1) 1 . 75 (2) 1 . 40 (3) 1 . 52 (4) 1 . 35

Q9. The resistances of the platinum wire of a platinum resistance thermometer at the ice point and steam point are 8Ω and 10Ω respectively. After inserting in a hot bath of temperature 400∘C , the resistance of platinum wire is : (1) 10Ω (2) 8Ω (3) 16Ω (4) 2Ω

Q9. Energy of 10 non rigid diatomic molecules at temperature T is : (1) 70 KBT (2) 35 KBT (3) 7 2 RT (4) 35RT

Q9. Two conductors have the same resistances at 0 °C but their temperature coefficients of resistance are 𝛼1 and 𝛼2 . The respective temperature coefficients for their series and parallel combinations are : (1) 𝛼1 + 𝛼2, 𝛼1 + 𝛼2 (2) 𝛼1 + 𝛼2 , 𝛼1 + 𝛼2 2 2 2 𝛼1 𝛼2 𝛼1 + 𝛼2 (4) (3) 𝛼1 + 𝛼2, , 𝛼1 + 𝛼2 2 𝛼1 + 𝛼2

Q10.Given below are two statements : Statement I : When a capillary tube is dipped into a liquid, the liquid neither rises nor falls in the capillary. The contact angle may be 0∘ . Statement II : The contact angle between a solid and a liquid is a property of the material of the solid and liquid as well. In the light of the above statement, choose the correct answer from the options given below. (1) Both Statement I and Statement II are false (2) Both Statement I and Statement II are true (3) Statement I is false but Statement II is true (4) Statement I is true and Statement II is false

Q10.A bulb and a capacitor are connected in series across an ac supply. A dielectric is then placed between the plates of the capacitor. The glow of the bulb: (1) increases (2) decreases (3) remains same (4) becomes zero

Q10. N moles of a polyatomic gas (f = 6) must be mixed with two moles of a monoatomic gas so that the mixture behaves as a diatomic gas. The value of N is: (1) 6 (2) 3 (3) 4 (4) 2 N C−1 . The electric flux through a surface area 30ˆi m2 lying in

Q10.An electric charge 10−6 μC is placed at origin (0, 0) m of X −Y co-ordinate system. Two points P and Q are situated at m and m respectively. The potential difference between the points P and Q (√3, √3) (√6, 0) will be : (1) √3 V (2) √6 V (3) 0 V (4) 3 V

Q10.Two moles of a monoatomic gas is mixed with six moles of a diatomic gas. The molar specific heat of the mixture at constant volume is : 9 7 (1) 4𝑅 (2) 4𝑅 (3) 3 (4) 5 2𝑅 2𝑅

Q10.Two identical conducting spheres P and S with charge Q on each, repel each other with a force 16 N. A third identical uncharged conducting sphere R is successively brought in contact with the two spheres. The new force of repulsion between P and S is : (1) 1 N (2) 6 N (3) 12 N (4) 4 N

Q10.Two charges of 5Q and −2Q are situated at the points (3a, 0) and (−5a, 0) respectively. The electric flux through a sphere of radius 4a having centre at origin is: (1) 2Q (2) 5Q ε0 ε0 (3) 7Q (4) 3Q ε0 ε0

Q10.The effective resistance between A and B, if resistance of each resistor is R, will be (1) 8R (2) 5R 3 3 (3) 4R (4) 2 R 3 3

Q10.A particle of charge -𝑞 and mass 𝑚 moves in a circle of radius 𝑟 around an infinitely long line charge of linear density +𝜆. Then time period will be given as: (Consider 𝑘 as Coulomb's constant) (1) 𝑇2 = 4𝜋2 2𝑘𝜆𝑞𝑟3𝑚 (2) 𝑇= 2𝜋𝑟√ 2𝑘𝜆𝑞𝑚 (3) 𝑇= 1 𝑚 (4) 𝑇= 1 2𝑘𝜆𝑞 2𝜋𝑟√ 2𝑘𝜆𝑞 2𝜋√ 𝑚

Q11.A proton and a deutron ( q = +e, m = 2.0u) having same kinetic energies enter a region of uniform magnetic field →B, moving perpendicular to →B. The ratio of the radius rd of deutron path to the radius rp of the proton path is: (1) √2 : 1 (2) 1 : 1 (3) 1 : √2 (4) 1 : 2

Q11.A capacitor has air as dielectric medium and two conducting plates of area 12 cm2 and they are 0.6 cm apart. When a slab of dielectric having area 12 cm2 and 0.6 cm thickness is inserted between the plates, one of the conducting plates has to be moved by 0.2 cm to keep the capacitance same as in previous case. The dielectric constant of the slab is : (Given ϵ0 = 8.834 × 10−12 F/m ) (1) 1 (2) 1.33 (3) 0.66 (4) 1.50

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.Two charged conducting spheres of radii a and b are connected to each other by a conducting wire. The ratio of charges of the two spheres respectively is: (1) a b v (2) √ab (3) b (4) ab a

Q11.A capacitor is made of a flat plate of area A and a second plate having a stair-like structure as shown in figure. If the area of each stair is A and the height is d, the capacitance of the arrangement is : 3 (1) 13ϵoA (2) 11ϵoA 17d 18 d (3) 18ϵoA (4) 11ϵoA 11 d 20 d

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. A galvanometer of resistance 100Ω when connected in series with 400Ω measures a voltage of upto 10 V. The value of resistance required to convert the galvanometer into ammeter to read upto 10 A is x × 10−2Ω. The value of x is : (1) 2 (2) 800 (3) 20 (4) 200