 # JEE Main Solved Practice Paper 2017 - 2018 Set - IV

Find solved practice paper (90 questions) for JEE Main 2018. It is prepared by Subject Experts after the detailed analysis of few previous years’ papers of JEE Main exam. JEE 2018: Solved Practice Paper

JEE Main 2018 is scheduled to be held on April 8, 2018 in offline mode while computer based test will be conducted on April 15 and 16, 2018.

It is very important for students to get familiar with the latest pattern and difficulty level before appearing for any engineering entrance examination. On the basis of pattern of the practice paper, students can make strategy to attempt the paper.

In this article, the engineering section of Jagranjosh is providing JEE Main Solved Practice Paper to help students in their preparation.

There are three sections in this paper namely Physics, Chemistry and Mathematics. Each section consists of 30 questions. The time allotted to complete the paper is 3 hours.

Physics

Here, you will get a set of 30 questions from different topics of Physics like Units and Measurements, Motion in a Straight Line, Laws of Motion, Rotational Motion, Gravitation, Thermodynamics, Kinetic Theory of gases, Waves, Electric Charges and Fields, Electrostatic Potential and Capacitance, Current Electricity, Moving Charges and Magnetism, Magnetism and Matter, Electromagnetic Induction & Alternating Current, Electromagnetic Induction, Alternating Current, Electromagnetic Waves, Dual Nature of Radiation and Matter, Atoms & Nuclei, Semiconductor  Electronics, Communication Systems. For each correct answer you will be award +4 marks and for each incorrect answer one mark will be deducted. Zero mark will be awarded for unattempted questions.

Few sample questions from the Physics practice paper are given below:

Question:

In a cyclotron, a charged particle

(a) Undergoes acceleration all the time

(b) Speeds up between the dees because of the magnetic field

(c) Speeds up in a dee

(d) Slows down within a dee and speeds up between dees

Sol. (a)

The charged particle undergoes acceleration as

(i) speeds up between the dees because of the oscillating electric field and

(ii) speed remain the same inside the dees because of the magnetic field but direction undergoes change continuously.

Question:

In a permanent magnet at room temperature,

(a) Magnetic moment of each molecule is zero

(b) The individual molecules have non - zero magnetic moment which are all perfectly aligned

(c) Domains are partially aligned

(d) Domains are all perfectly aligned

Sol. (d)

As we know a permanent magnet is a substance which at room temperature retains ferromagnetic property for a long period of time. The individual atoms in a ferromagnetic material possess a dipole moment as in a paramagnetic material.

However, they interact with one another in such a way that they spontaneously align themselves in a common direction over a macroscopic volume called domain. Thus, we can say that in a permanent magnet at room temperature, domains are all perfectly aligned.

Mathematics

Mathematics is one of the most scoring subjects among three. For each correct answer +4 marks will be awarded and one mark will be deducted for each incorrect answer. Zero marks will be awarded for any unattempted question. There are 30 questions in this practice paper from different topics like Sets, Relations and Functions, Trigonometric Functions, Complex Numbers and Quadratic Equations, Linear Inequalities, Permutations and Combinations, Binomial Theorem, Sequences and Series, Straight Lines, Conic Sections, Limits and Derivatives, Probability, Inverse Trigonometric Functions, Matrices, Determinants, Continuity and Differentiability, Application of Derivatives, Integrals, Application of Integrals, Differential Equations, Vector Algebra, Three Dimensional Geometry.

Few sample questions from the Mathematics practice paper are given below:

Question:

A ladder, 5 m long, standing on a horizontal floor, leans against a vertical wall. If the top of the ladder slides downwards at the rate of 10 cm/s, then the rate at which the angle between the floor and the ladder is decreasing when lower end of ladder is 2 m from the wall is

Sol.(b)

Let the angle between floor and the ladder be q.

Let AB = x cm and BC = y cm Question:

Three dice are thrown at the same time. The probability of getting three two’s, if it is known that the sum of the numbers on the dice was six is

(a) 1/5

(b) 1/8

(c) 1/12

(d) 1/10

Sol.(d)

On a throw of three dice, we have sample space [n(S)] = 63 = 216

Let E1 is the event when the sum of numbers on the dice was six and E2 is the event when three two’s occurs.

⇒  (E1 = {(1, 1, 4), (1, 2, 3), (1, 3, 2), (1, 4, 1), (2, 1, 3) (2, 2, 2), (2, 3, 1),(3, 1, 2), (3, 2, 1), (4, 1, 1)

⇒        n(E1) = 10 and E2 ={2, 2, 2}

⇒        n(E11

Also,    (E1 ∩ E2) = 1 Chemistry

The marking scheme and number of questions are exactly same as other section of the sample paper. There are 30 questions in this practice paper from different topics of Chemistry like Basic Concepts of Chemistry, Structure of Atom, Chemical Bonding and Molecular Structure, States of Matter, Thermodynamics, Solid State, Solutions, Electrochemistry, Chemical Kinetics, Surface Chemistry, Isolation of Elements, p-Block Elements, d and f-Block Elements, Coordination Compounds, Haloalkanes and Haloarenes, Alcohols, Phenols and Ethers, Aldehydes, Ketones and Carboxylic Acids, Organic Compounds containing Nitrogen, Biomolecules, Polymers, Chemistry in Everyday Life.

Few sample questions from the Chemistry practice paper are given below:

Question:

Which one of the following statements related to lanthanons is incorrect?

(a) Europium shows +2 oxidation state.

(b) The basicity decreases as the ionic radius decreases from Pr to Lu.

(c) All the lanthanons are much reactive than aluminium.

(d) Ce (+4) solutions are widely used as oxidizing agent in volumetric analysis.

Sol. (d)

The first few members of the lanthanoid series are quite reactive, almost like calcium. However, with increasing atomic number, their behavior becomes similar to that of aluminium.

Question:

Which of the following process is not responsible for the presence of electric charge on the sol particles?

(a) Electron capture by sol particles

(b) Adsorption of ionic species from solution

(c) Formation of Helmholtz electrical double layer

(d) Absorption of ionic species from solution

Sol. (d)

Absorption of ionic species from solution is not responsible for the presence of electric charge on the sol particles. Charge on the sol particles is due to

(i) electrons capture by sol particles during electro dispersion of metal.

(ii) preferential adsorption of ionic species from solution.

(iii) formation of Helmholtz electrical double layer.

Conclusion:

After practicing this solved paper, students will have good idea about the different varieties of questions. It will also help students to maintain speed and accuracy in the examination.