Practice Questions
14,828 questions across 23 years of JEE Main — find and practise any topic!
Q87.Statement-1: The point A(3, 1, 6) is the mirror image of the point B(1, 3, 4) in the plane x −y + z = 5. Statement-2: The plane x −y + z = 5 bisects the line segment joining A(3, 1, 6) and B(1, 3, 4). (1) Statement-1 is true, Statement-2 is true; (2) Statement-1 is true, Statement-2 is false Statement-2 is not the correct explanation for Statement-1 (3) Statement-1 is false, Statement-2 is true (4) Statement-1 is true, Statement-2 is true; Statement-2 is the correct explanation for Statement-1 JEE Main 2010 JEE Main Previous Year Paper
Q88.A line AB in three-dimensional space makes angles 45∘ and 120∘ with the positive x-axis and the positive y- axis respectively. If AB makes an acute angle θ with the positive z-axis, then θ equals (1) 45∘ (2) 60∘ (3) 75∘ (4) 30∘
Q89.Four numbers are chosen at random (without replacement) from the set {1, 2, 3, … . , 20} . Statement-1: The probability that the chosen numbers when arranged in some order will form an AP is 1 . Statement-2: If the 85 four chosen numbers from an AP, then the set of all possible values of common difference is {±1, ±2, ±3, ±4, ±5}. (1) Statement-1 is true, Statement-2 is true; (2) Statement-1 is true, Statement-2 is false Statement-2 is not the correct explanation for Statement-1 (3) Statement-1 is false, Statement-2 is true (4) Statement-1 is true, Statement-2 is true; Statement-2 is the correct explanation for Statement-1
Q90.An urn contains nine balls of which three are red, four are blue and two are green. Three balls are drawn at random without replacement from the urn. The probability that the three balls have different colour is (1) 2 (2) 1 7 21 (3) 2 (4) 1 23 3 JEE Main 2010 JEE Main Previous Year Paper
Q1. A particle has an initial velocity 3^i + 4^j and an acceleration of 0.4^i + 0.3^j. Its speed after 10 s is (1) 10 units (2) 7√2 units (3) 7 units (4) 8.5 units
Q2. Consider a rubber ball freely falling from a height h = 4.9 m onto a horizontal elastic plate. Assume that the duration of collision is negligible and the collision with the plate is totally elastic. Then the velocity as a function of time the height as function of time will be (1) (2) (3) (4)
Q3. A thin uniform rod of length ℓ and mass m is swinging freely about a horizontal axis passing through its end. Its maximum angular speed is ω. Its centre of mass rises to a maximum height of (1) 1 ℓ2ω2 (2) 1 ℓω 3 g 6 g (3) 1 ℓ2ω2 (4) 1 ℓ2ω2 2 g 6 g
Q4. The height at which the acceleration due to gravity becomes g (where g = the acceleration due to gravity on 9 the surface of the earth) in terms of R, the radius of the earth is (1) 2R (2) R √2 (3) R (4) √2R 2
Q5. Two wires are made of the same material and have the same volume. However wire 1 has crosssectional area A and wire-2 has cross-sectional area 3A. If the length of wire 1 increases by Δx on applying force F , how much force is needed to stretch wire 2 by the same amount? (1) F (2) 4 F (3) 6 F (4) 9 F
Q6. A long metallic bar is carrying heat from one of its ends to the other end under steady-state. The variation of temperature θ along the length x of the bar from its hot end is best described by which of the following figure. (1) (2) (3) (4) JEE Main 2009 JEE Main Previous Year Paper
Q7. Assuming the gas to be ideal the work done on the gas in taking it from A to B is (1) 200R (2) 300R (3) 400R (4) 500R
Q8. The work done on the gas in taking it from D to A is (1) −414R (2) +414R (3) −690R (4) +690R
Q9. The net work done on the gas in the cycle ABCDA is (1) Zero (2) 276R (3) 1076R (4) 1904R
Q10.One kg of a diatomic gas is at a pressure of 8 × 104 N/m2 . The density of the gas is 4 kg/m−3 . What is the energy of the gas due to its thermal motion? (1) 3 × 104 J (2) 5 × 104 J (3) 6 × 104 J (4) 7 × 104 J
Q11.If x, v and a denote the displacement, the velocity and the acceleration of a particle executing simple harmonic motion of time period T, then, which of the following does not change with time? (1) a2T 2 + 4π2v2 (2) aTx (3) aT + 2πv (4) aTv
Q12.A motor cycle starts from rest and accelerates along a straight path at 2 m/s2 . At the starting point of the motor cycle there is a stationary electric sire. How far has the motor cycle gone when the driver hears the frequency of the siren at 94% of its value when the motor cycle was at rest? (speed of sound = 330 ms−1) (1) 49 m (2) 98 m (3) 147 m (4) 196 m
Q13.Three sound waves of equal amplitudes have frequencies (v −1), v, (v + 1). They superpose to give beats. The number of beats produced per second will be (1) 4 (2) 3 (3) 2 (4) 1
Q14.This question contains Statement-1 and Statement-2. Of the four choices given after the statements, choose the one that best describes the two statements. Statement - 1: For a charged particle moving from point P to point Q, the net work done by an electrostatic field on the particle is independent of the path connecting point P to point Q. Statement-2: The net work done by a conservative force on an object moving along a closed loop is zero (1) Statement-1 is true, Statement-2 is false (2) Statement-1 is true, Statement-2 is true; Statement-2 is the correct explanation of Statement-1. (3) Statement-1 is true, Statement-2 is true; (4) Statement-1 is false, Statement-2 is true Statement-2 is not the correct explanation of Statement-1.
Q15.Let P(r) = Q r be the charge density distribution for a solid sphere of radius R and total charge Q. for a πR4 point ' p ' inside the sphere at distance r1 from the centre of the sphere, the magnitude of electric field is JEE Main 2009 JEE Main Previous Year Paper (1) 0 (2) Q 4πε0r21 (3) Qr21 (4) Q21 4πε0R4 3πε0R4
Q16.Two points P and Q are maintained at the potentials of 10 V and −4 V respectively. The work done in moving 100 electrons from P to Q is (1) −19 × 10−17 J (2) 9.60 × 10−17 J (3) −2.24 × 10−16 J (4) 2.24 × 10−16 J
Q17.A charge Q is placed at each of the opposite corners of a square. A charge q is placed at each of the other two corners. If the net electrical force on Q is zero, then the Q/q equals (1) −2√2 (2) −1 (3) 1 (4) −1 √2
Q18.This question contains Statement-1 and Statement-2. Of the four choices given after the statements, choose the one that best describes the two statements. Statement-1: The temperature dependence of resistance is usually given as R = R0(1 + αΔt). The resistance of a wire changes from 100Ω to 150Ω when its temperature is increased from 27∘C to 227∘C. This implies that α = 2.5 × 10−3/∘C. Statement 2: R = Ri(1 + αΔT) is valid only when the change in the temperature ΔT is small and ΔR = (R −R0) ≪R0 . (1) Statement-1 is true, Statement-2 is false (2) Statement-1 is true, Statement-2 is true; Statement-2 is the correct explanation of Statement-1. (3) Statement-1 is true, Statement-2 is true; (4) Statement-1 is false, Statement-2 is true Statement-2 is not the correct explanation of Statement-1.
Q19.The magnitude of the magnetic field (B) due to loop ABCD at the origin (O) is (1) zero (2) μ0(b−a) 24ab (3) μ0I 4π [ b−aab ] (4) μo∣4π [2(b −a) + π3 (a + b)]
Q20.Due to the presence of the current l1 at the origin (1) The forces on AB and DC are zero (2) The forces on AD and BC are zero (3) The magnitude of the net force on the loop is (4) The magnitude of the net force on the loop is given by μ0I1 4π [2(b −a) + π3 (a + b)] given by μ0∥124ab (b −a)
Q21.An inductor of inductance L = 400mH and resistors of resistances R1 = 2Ω and R2 = 2Ω are connected to a battery of emf 12 V as shown in the figure. The internal resistance of the battery is negligible. The switch S is closed at t = 0. The potential drop across L as a function of time is (1) 6e−5tV (2) 12t e−3tV (3) 6 (1 −e−t/0.2)V (4) 12e−5tV JEE Main 2009 JEE Main Previous Year Paper