Total Number of Question/s - 3094

Just Exam provide question bank for JEE MAIN standard. Currently number of question's are 3094. We provide this data in all format (word, excel, pdf, sql, latex form with images) to institutes for conducting online test/ examinations. Here we are providing some demo contents.
Interested person may contact us at info@justexam.in

• 1. Measurements - Quiz

SAMPLE QUESTIONS

1. A body of mass m= 3.513 kg is moving along the x-axis with a speed of 5.00 ms-1. The magnitude of its momentum is recorded as
a) 17.6 kg ms-1
b) 17.565 kg ms-1
c) 17.56 kg ms-1
d) 17.57 kg ms-1

2. The respective number of significant figures for the numbers 23.023, 0.0003 and 21 x 10-3 are
a) 5, 1, 2
b) 5, 1, 5
c) 5, 5, 2
d) 4, 4, 2

• 2. Kinematics - Quiz

SAMPLE QUESTIONS

1. Speeds of two identical cars are u and 4 u at a specific instant. The ratio of the respective distances at which the two cars are stopped from that instant is
a) 1: 1
b) 1 : 4
c) 1 : 8
d) 1 : 16

2. The relation between time t and distance x is t = ax2 + bx, where a and b are constants. The acceleration is
a) -2 abv2
b) 2 bv3
c) - 2av3
d) 2 av2

• 3. Laws of Motion - Quiz

SAMPLE QUESTIONS

1. Consider the following two statements :
A. Linear momentum of a system of particles is zero.
B. Kinetic energy of a system of particles is zero
Then
a) A does not imply B and B does not imply A
b) A implies B but B does not imply A
c) A does not imply B but B implies A
d) A implies B and B implies A

2. A horizontal force of 10 N is necessary to just hold a block stationary against a wall. The coefficient of friction between the block and the wall is 0.2. The weight of the block is

a) 20 N
b) 50 N
c) 100 N
d) 2 N

• 4. Work, Energy and Power - Quiz

SAMPLE QUESTIONS

1. A spring of spring constant 5 x 103 N/m is stretched initially by 5 cm from the unstretched it position. Then the work required to stretch it further by another 5 cm is
a) 12.50 N-m
b) 18.75 N-m
c) 25.00 N-m
d) 6.25 N-m

2. A spring of force constant 800 N/m has an extension of 5 cm. The work done in extending it from 5 cm to 15 cm is
a) 16 J
b) 8 J
c) 32 J
d) 24 J

• 5. Rotational Motion - Quiz

SAMPLE QUESTIONS

1. One solid sphere A and another hollow sphere B are of same mass and same radii. Their moment of interia about their diameter are respectively IA and IB such that
a) IA = IB
b) IA > IB
c) IA < IB
d) $\frac{1}{2}Mt^{2}$

2. A round uniform body of radius R, mass M and moment of interia I, rolls down ( without slipping) an inclined plane making an angle θ with the horizontal. Then its acceleration is
a) $\frac{g sin\theta}{1 + I/MR^{2}}$
b) $\frac{g sin\theta}{1 + MR^{2}/I}$
c) $\frac{R sin\theta}{1 - I/MR^{2}}$
d) $\frac{g sin\theta}{1 - MR^{2}/I}$

• 6. Gravitation - Quiz

SAMPLE QUESTIONS

1. The change in the value of g at a height h above the surface of the earth is the same as at a depth d below the surface of earth. When both d and h are much smaller than the radius of earth, then which one of the following is correct?
a) d = $\frac{h}{2}$
b) d = $\frac{3h}{2}$
c) d = 2h
d) d = h

2. The height at which the acceleration due to gravity becomes $\frac{g}{9}$ (where g = the acceleration due to gravity on the surface of the earth) in terms of R, the radius of the earth is
a) 2R
b) $\frac{R}{\sqrt{3}}$
c) $\frac{R}{2}$
d) $\sqrt{2}R$

• 7. Properties of Solids and Liquids - Quiz

SAMPLE QUESTIONS

1. A wire elongates by l mm when a load w is hanged from it. If the wire goes over a pulley and two weights w each are hung at the two ends, the elongation of the wire will be (in mm)
a) l
b) 2l
c) Zero
d) $\frac{l}{2}$

2. Spherical balls of radius R are falling in a viscous fluid of viscosity η with a velocity v. The retarding viscous force acting on the spherical ball is
a) Directly proportional to R but inversely proportional to v
b) Directly proportional to both radius R and velocity v
c) Inversely proportional to both radius R and velocity v
d) Inversely proportional to R but directly proportional to velocity v

• 8. Thermodynamics - Quiz

SAMPLE QUESTIONS

1. Which of the following statements is correct for any thermodynamics system?
a) The internal energy changes in all processes.
b) Internal energy and entropy are state functions.
c) The change in entropy can never be zero .
d) The work done in an adiabatic process is always zero.

2. A log metallic bar is carrying heat from one of its end to the order 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.
a)
b)
c)
d)

• 9. Kinetic Theory of Gases - Quiz

SAMPLE QUESTIONS

1. One kg of a diatomic gas is at a pressure of 8 × 10-4 Nm-2 . The density of the gas is 4 kgm-3. What is the energy of the gas due to its thermal motion?
a) 3 × 104 J
b) 5 × 104 J
c) 6 × 104 J
d) 7 × 104 J

2. Three perfect gases at absolute temperatures T1, T2 and T3 are mixed. The masses of molecules are m1, m2 and m3 and the number of molecules are n1, n2 and n3 respectively . Assuming no loss of energy, the final temperature of the mixture is
a) $\frac{n_{1}T_{1} + n_{2}T_{2} + n_{3}T_{3}}{n_{1}+ n_{2} + n_{3}}$
b) $\frac{n_{1}T_{1}^{2} + n_{2}T_{2}^{2} + n_{3}T_{3}^{2}}{n_{1}T_{1}+ n_{2}T_{2} + n_{3}T_{3}}$
c) $\frac{n_{1}^{2}T_{1}^{2} + n_{2}^{2}T_{2}^{2} + n_{3}^{2}T_{3}^{2}}{n_{1}T_{1}+ n_{2}T_{2} + n_{3}T_{3}}$
d) $\frac{\left ( T_{1} + T_{2} + T_{3} \right )}{3}$

• 10. Oscillations and Waves - Quiz

SAMPLE QUESTIONS

1. Two spring of force constants k1 and k2, are connected to a mass m as shown. The frequency of oscillation of the mass is f. If both k1 and k2 are made four times their original values, the frequency of oscillation becomes

a) $\frac{f}{2}$
b) $\frac{f}{4}$
c) 4f
d) 2f

2. A string is stretched between fixed points separated by 75.0 cm. It is observed to have resonant frequencies of 420 Hz and 315 Hz. There are no other resonant frequencies between these two. Then, the lowest resonant frequency for this string is
a) 105 Hz
b) 1.05 Hz
c) 1050 Hz
d) 10.5 Hz

• 11. Electrostatics - Quiz

SAMPLE QUESTIONS

1. A parallel plate capacitor with air between the plates has a capacitance of 9pF. The separation between its plates is d. The space between the plate is now filled with two dielectrics. One the plate is now dielectric constant K1 = 3 and thickness $\frac{d}{3}$ while the other one has dielectric constant K2 = 6 and thickness $\frac{2d}{3}$. Capacitance of the capacitor is now
a) 1.8 pF
b) 45 pF
c) 40.5 pF
d) 20.25 pF

2. Two positive charges of magnitude q are placed at the ends of a side 1 square of side 2a. Two negative charges of the same magnitude are kept at the other corners. Starting from rest, if a charge Q moves from the middle of side 1 to the centre of square, its kinetic energy at the centre of square is
a) $\frac{1}{4\pi \epsilon_{0}}\frac{2qQ}{a}\left (1 - \frac{1}{\sqrt{5}} \right )$
b) zero
c) $\frac{1}{4\pi \epsilon_{0}}\frac{2qQ}{a}\left (1 + \frac{1}{\sqrt{5}} \right )$
d) $\frac{1}{4\pi \epsilon_{0}}\frac{2qQ}{a}\left (1 - \frac{2}{\sqrt{5}} \right )$

• 12. Current Electricity - Quiz

SAMPLE QUESTIONS

1. Time taken by a 836W heater to heat one litre of water from 100C to 400C is
a) 50 s
b) 100 s
c) 150 s
d) 200 s

2. A 220V, 1000W bulb is connected across a 110V mains supply. The power consumed will be
a) 750 W
b) 500 W
c) 250 W
d) 1000W

• 13. Magnetic Effects of Current and Magnetism - Quiz

SAMPLE QUESTIONS

1. Two identical conducting wires AOB and COD are placed at right angle to each other. The wire AOB carries an electric current I1 and COD carries a current I2. The magnetic field on a point lying at a distance d from O, in a direction perpendicular to the plane of the wires AOB and COD, will be given by
a) $\frac{\mu_{0}}{2\pi}\left (\frac{I_{1} + T_{2}}{d} \right )^{1/2}$
b) $\frac{\mu_{0}}{2\pi d}\left (I_{1}^{2} + I_{2}^{2} \right )^{1/2}$
c) $\frac{\mu_{0}}{2\pi d}\left (I_{1} + I_{2} \right )$
d) $\frac{\mu_{0}}{2\pi d}\left (I_{1}^{2} + I_{2}^{2} \right )$

2. A thin circular disk of radius R is uniformly charged with density σ > 0 per unit area. The disk rotates about its axis with a uniform anguilar speed ω. The magnetic moment of the disk is
a) 2πR4ω
b) πR4σω
c) $\frac{\pi R^{4}}{2}\sigma \omega$
d) $\frac{\pi R^{4}}{4}\sigma \omega$

• 14. Electromagnetic Induction and Alternating Current - Quiz

SAMPLE QUESTIONS

1. In an LCR circuit, capacitance is changed from C to 2C. For the resonant frequency to remain unchanged, the inductance should be changed from L to
a) 4L
b) 2L
c) L/2
d) L/4

2. In an oscillating LC circuit the maximum charge on the capacitor is Q. The charge on the capacitor when the energy is stored equally between the electrcic and magnetic fields is
a) $\frac{Q}{2}$
b) $\frac{Q}{\sqrt{3}}$
c) $\frac{Q}{\sqrt{2}}$
d) Q

• 15. Electromagnetic Waves - Quiz

SAMPLE QUESTIONS

1. Which of the following are not electromagnetic waves?
a) Cosmic-rays
b) γ-rays
c) β-rays
d) X-rays

2. An electromagnetic wave of frequency v = 3.0 MHz passes from vacuum into a dielectric medium and permittivity ε = 4.0. Then
a) wavelength is doubled and the frequency remains unchanged
b) wavelength is doubled and frequency becomes half
c) wavelength is halved and frequency remains unchanged
d) wavelength and frequency both remain unchanged

• 16. Optics - Quiz

SAMPLE QUESTIONS

1. A student measures the focal length of a convex lens by putting an object pin at a distance u from the lens and measuring the distance v of the image pin. The graph between u and v plotted by the student should look like
a)
b)
c)
d)

2. The maximum number of possible interference maxima for slit-separation equal to twice the wavelength in Youngs double slit experiment, is
a) infinite
b) five
c) three
d) zero

• 17. Dual Nature of Matter and Radiation - Quiz

SAMPLE QUESTIONS

1. Wave property of electrons implies that they will slow diffraction effects. Davisson and Germer demonstrated this by diffracting effects .Davisson and Germer demonstrated this by diffracting electrons from crystal. The law governing the diffraction from a crystal is obtained by requiring that electron waves reflected from the planes of atoms in a crystal interfere construtively (see figure)

Electrons accelerated by potential V are diffracted from a crystal . If d = 1Å and I = 300, V should be about (h = 6.6 x 10-34 J-s, me = 9.1 x 10-31 kg, e = 1.6 x 10-19C)
a) 2000 V
b) 50V
c) 500V
d) 1000V

2. Sodium and copper have work functions 2.3 eV and 4.5 eV respectively. Then the ratio of the wavelengths is nearest to
a) 1:2
b) 4:1
c) 2:1
d) 1:4

• 18. Atoms and Nuclei - Quiz

SAMPLE QUESTIONS

1. The binding energy per nucleon of deutron $\left (^{2}_{1}H \right )$ and helium $\left (^{4}_{2}He \right )$ is 1.1 MeV and 7MeV respectively. It two deutron nuclei react to form a single helium nucleus, then the energy released is
a) 13.9 MeV
b) 26.9MeV
c) 23.6MeV
d) 19.2MeV

2. Which of the following atoms has the lowest ionization potential?
a)
b)
c)
d)

• 19. Electronic Devices - Quiz

SAMPLE QUESTIONS

1. When npn transistor is used as an amplifier
a) electrons move from base to collector
b) holes move from either to base
c) electrons move from collector to base
d) holes move from base to emiiter

2. A solid which is not transparent to visible light and whose conductivity increases with temperature is formed by
a) ionic binding
b) covalent binding
c) van der Waals binding
d) metallic binding

• 20. Communication Systems - Quiz

SAMPLE QUESTIONS

1. Consider telecommunication through optical fibres. Which of the following statements is not true?
a) Optical fibres can be graded refractive index
b) Optical fibres are subjected to electromagnetic interference from outside
c) Optical fibres have extremely low transmission loss
d) Optical fibres may have homogeneous core with a suitable cladding

2. The logic circuit shown below has the input waveforms A and B as shown. Pick out the correct output wavefrom.

a)
b)
c)
d)

Available Class/Courses
Social Connectivity