Practice Questions

Q19.In the given circuit if the power rating of Zener diode is 10 mW, the value of series resistance 𝑅𝑠 to regulate the input unregulated supply is: 3 (1) 𝑘𝛺 (2) 10 𝛺 7 (3) 1 𝑘𝛺 (4) 10 𝑘𝛺 Q20.10 divisions on the main scale of a Vernier calliper coincide with 11 divisions on the Vernier scale. If each division on the main scale is of 5 units, the least count of the instrument is : (1) 1 (2) 10 2 11 (3) 50 (4) 5 11 11

Q19.The correct truth table for the following logic circuit is : (1) A B Y (2) A B Y 0 0 1 0 0 0 0 1 1 0 1 1 1 0 0 1 0 0 1 1 1 1 1 1 (3) A B Y (4) A B Y 0 0 1 0 0 0 0 1 1 0 1 0 1 0 0 1 0 0 1 1 0 1 1 1

Q20.The truth table for this given circuit is: JEE Main 2024 (29 Jan Shift 2) JEE Main Previous Year Paper (1) (2) (3) (4)

Q20.Conductivity of a photodiode starts changing only if the wavelength of incident light is less than 660 nm . X The band gap of photodiode is found to be eV . The value of X is: 8 (Given h = 6 . 6 × 10-34 J s, e = 1 . 6 × 10-19 C) (1) 15 (2) 11 (3) 13 (4) 21

Q20. In the truth table of the above circuit the value of X and Y are : (1) 0,0 (2) 1,1 (3) 1,0 (4) 0,1

Q20.Which of the diode circuit shows correct biasing used for the measurement of dynamic resistance of p-n junction diode : (1) (2) (3) (4)

Q20.In the given circuit, the breakdown voltage of the Zener diode is 3. 0 V. What is the value of Iz ? JEE Main 2024 (29 Jan Shift 1) JEE Main Previous Year Paper (1) 3. 3 mA (2) 5. 5 mA (3) 10 mA (4) 7 mA

Q20.Following gates section is connected in a complete suitable circuit. For which of the following combination, bulb will glow (ON) : (1) A = 0, B = 0, C = 0, D = 1 (2) A = 0, B = 1, C = 1, D = 1 (3) A = 1, B = 0, C = 0, D = 0 (4) A = 1, B = 1, C = 1, D = 0

Q20.A Zener diode of breakdown voltage 10 V is used as a voltage regulator as shown in the figure. The current through the Zener diode is (1) 50 mA (2) 0 (3) 30 mA (4) 20 mA

Q20.One main scale division of a vernier caliper is equal to m units. If nth division of main scale coincides with (n + 1)th division of vernier scale, the least count of the vernier caliper is : (1) n (2) 1 (n+1) (n+1) (3) m (4) m (n+1) n(n+1) 5 for |→a| = n|→b| The integer

Q20.There are 100 divisions on the circular scale of a screw gauge of pitch 1 mm . With no measuring quantity in between the jaws, the zero of the circular scale lies 5 divisions below the reference line. The diameter of a wire is then measured using this screw gauge. It is found that 4 linear scale divisions are clearly visible while 60 divisions on circular scale coincide with the reference line. The diameter of the wire is : (1) 3.35 mm (2) 4.65 mm (3) 4.55 mm (4) 4.60 mm

Q20.A vernier callipers has 20 divisions on the vernier scale, which coincides with 19th division on the main scale. The least count of the instrument is 0.1 mm. One main scale division is equal to _____ mm . (1) 0.5 (2) 2 (3) 5 (4) 1

Q31.Match List I with List II Choose the correct answer from the options given below :- (1) A-II, B-III, C-I, D-IV (2) A-I, B-III, C-II, D-IV (3) A-II, B-IV, C-III, D-I (4) A-I, B-II, C-III, D-IV

Q31.An organic compound has 42.1% carbon, 6.4% hydrogen and remainder is oxygen. If its molecular weight is 342, then its molecular formula is : (1) C11H18O12 (2) C12H20O12 (3) C12H22O11 (4) C14H20O10

Q31.Which of the following cannot function as an oxidising agent? (1) N3 - (2) SO42 - (3) BrO3- (4) MnO4-

Q31.Molality ( m ) of 3M aqueous solution of NaCl is : (Given : Density of solution = 1.25 g mL−1 , Molar mass in gmol−1 : Na −23, Cl −35.5) JEE Main 2024 (06 Apr Shift 2) JEE Main Previous Year Paper (1) 1.9 m (2) 3.85 m (3) 2.79 m (4) 2.90 m

Q31.The density of ' x ' M solution (' X ' molar) of NaOH is 1.12 g mL−1 , while in molality, the concentration of the solution is 3 m(3molal). Then x is (Given : Molar mass of NaOH is 40 g/mol ) (1) 3.5 (2) 3.8 (3) 2.8 (4) 3.0

Q31.Number of elements from the following that CANNOT form compounds with valencies which match with their respective group valencies is ______. B, C, N, S, O, F, P, Al, Si (1) 7 (2) 3 (3) 5 (4) 6

Q31.A sample of CaCO3 and MgCO3 weighed 2 .21 g is ignited to constant weight of 1 .152 g. The composition of the mixture is: (Given molar mass in g mol−1, CaCO3: 100, MgCO3: 84) (1) 1 .187 𝑔 𝐶𝑎𝐶𝑂3 + 1 .023 𝑔 𝑀𝑔𝐶𝑂3 (2) 1 .023 𝑔 𝐶𝑎𝐶𝑂3 + 1 .023 𝑔 𝑀𝑔𝐶𝑂3 (3) 1 .187 𝑔 𝐶𝑎𝐶𝑂3 + 1 .187 𝑔 𝑀𝑔𝐶𝑂3 (4) 1 .023 𝑔 𝐶𝑎𝐶𝑂3 + 1 .187 𝑔 𝑀𝑔𝐶𝑂3

Q31.Identify the correct statements about p-block elements and their compounds. (A) Non metals have higher electronegativity than metals. (B) Non metals have lower ionisation enthalpy than metals. (C) Compounds formed between highly reactive nonmetals and highly reactive metals are generally ionic. (D) The non-metal oxides are generally basic in nature. (E) The metal oxides are generally acidic or neutral in nature. Choose the correct answer from the options given below : (1) (B) and (D) only (2) (A) and (C) only (3) (D) and (E) only (4) (B) and (E) only

Q31.The correct sequence of electron gain enthalpy of the elements listed below is A. Ar B. Br C. F D. S Choose the most appropriate from the options given below: (1) C > B > D > A (2) A > D > B > C (3) A > D > C > B (4) D > C > B > A

Q32.The element having the highest first ionization enthalpy is (1) Si (2) Al (3) N (4) C

Q32.The electron affinity value are negative for A. Be →Be− B. N →N− C. O →O2− D. Na →Na− E. Al →Al− Choose the most appropriate answer from the options given below : (1) D and E only (2) A, B and C only (3) A and D only (4) A, B, D and E only

Q32.The electronic configuration of Einsteinium is : (Given atomic number of Einsteinium = 99) (1) [Rn]5f 106 d∘7 s2 (2) [Rn]5f 136 d∘7 s2 (3) [Rn]5f 116 d∘7 s2 (4) [Rn]5f 126 d∘7 s2

Q32.The correct order of the first ionization enthalpy is (1) Al > Ga > Tl (2) Ga > Al > B (3) Tl > Ga > Al (4) B > Al > Ga