Engineering Questions — JEE Main
379 solved questions with detailed explanations
Q.14. Let and . If is a vector such that and , then is equal to :
Q.44. Two radioactive substances A and B of mass numbers 200 and 212 respectively, shows spontaneous α-decay with same Q value of 1 MeV. The ratio of energies of α-rays produced by A and B is
Q.39. The maximum rated power of the LED is 2 mW and it is used in the circuit with input voltage of 5 V as shown in the figure below. The current through resistance is 0.5 mA. The minimum value of t
Q.64. Identify the correct IUPAC name of hydrocarbon (x) containing three primary carbon atoms and with molar mass 72 g mol⁻¹.
Q.41. The energy of an electron in an orbit of the Bohr's atom is eV where is the ground state energy. If L is the angular momentum of the electron in this orbit and h is the Planck's constant, then
Q.53. is isostructural with : Choose the correct answer from the options given below:
Q.14. If is the image of in the line , then the possible value(s) of is(are) :
Q.60. Given below are two statements : Statement I: The number of pairs among [Ti, V], [V, Mn], [Mn, Fe] and [V, Cr] in which both ions are coloured is 3. Statement II: The number pairs among [La, Yb]
Q.57. Match List-I with List-II. List-I (Reagents) A. H, Pd-BaSO B. SnCl, HCl C. CrOCl, CS D. CO, HCl, Anhyd. AlCl List-II (Reaction Name (Involving aldehydes)) I. Etard Reaction II. Rosenmund Reducti
Q.51. The ratio of mass percentage (w/w) of C : H in a hydrocarbon is 12 : 1. It has two carbon atoms. The weight (in g) of formed when 3.38 g of this hydrocarbon is completely burnt in oxygen is : (
Q.55. 20 mL of a solution of acetic acid required 28.4 mL of 0.1 M NaOH for its neutralization. A solution (X) was prepared by mixing 20 mL of the above acetic acid and 14.2 mL of 0.1 M NaOH solution.
Q.46. A copper wire of length 3 m is stretched by 3 mm by applying an external force. The volume of the wire is m³. The elastic potential energy stored in the wire in stretched condition would be J.
Q.59. Find the correct statements related to group 15 hydrides. A. Reducing nature increases from NH₃ to BiH₃ B. Tendency to donate lone pair of electrons decreases from NH₃ to BiH₃ C. The stability o
Q.69. Among Fe³⁺, Pb²⁺, Cu²⁺ and Mn²⁺, identify the one that gets precipitated out while passing H₂S in presence of NH₄OH as group reagent. The highest possible oxidation state of the corresponding me
Q.64. Given below are two statements : Statement-I : 2, 6-diethylcyclohexanone and 6-methyl-2-n-propylcyclohexanone are metamers. Statement-II: 2, 2, 6, 6-tetramethylcyclohexanone exhibits keto-enol t
Q.45. Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R. Assertion A: A diode under reverse-biased condition provides very small current which is nea
Q.6. The number of seven-digit numbers, that can be formed by using the digits 1, 2, 3, 5 and 7 such that each digit is used at least once, is :
Q.51. An oxide of iron contains 69.9% iron, its empirical formula, is: (Given : Molar mass of Fe and O are 56 and 16 g mol respectively.)
Q.50. A diatomic gas () does 100 J of work when it is expanded isobarically. Then the heat given to the gas .......... J.
Q.60. Consider the metal complexes [Ni(en)] (A), [NiCl] (B) and [Ni(NH)] (C). Choose the CORRECT option by considering the number of unpaired electron present in (A), (B) and (C) respectively and the