Total Number of Question/s - 5154

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  • 1. Electric Charges and Fields - Quiz


    SAMPLE QUESTIONS


    1. Uniform electric field exists in a region and is given by$\vec{E} = E_{0}\hat{i} + E_{0}\hat{j}$ There are four points A (-a,0), B(0,-a), C(a,0), and D(0,a) in the xy plane. Which of the following is the correct relation for the electric potential?
    a) VA = $V_{C} > V_{B}$ = $V_{D}$
    b) $V_{A}$ = $V_{B} > V_{C}$ = $V_{D}$
    c) $V_{A}$ >$V_{B} > V_{C}$ = $V_{D}$
    d) $V_{A}$ < $V_{B} < V_{C}$ < $V_{D}$

    2. Two point charges +Q each have been placed at the positions (-a/2,0,0) and (a/2,0,0). The locus of the points where -Q charge can be placed such that total electrostatic potential energy of the system can become equal to zero, can be represented by which of the following equations?
    a) z2 + (y - a)2 = 2a
    b) z2 + (y - a)2 = 27a2/4
    c) z2 + y2 = 15a2/4
    d) none of these

  • 2. Electrostatic Potential and Capacitance - Quiz


    SAMPLE QUESTIONS


    1. Two points P and Q are maintained at the potentials of 10 V and -4 V respectively. Work done in moving 100 electrons from P to Q is
    a) -19 x 10-17J
    b) 9.60 x 10-17 J
    c) -2.24 x 10-16 J
    d) 2.24 x 10-16 J

    2. Equipotential surface associated with an electric field which is increasing in magnitude along the x-direction are
    a) Planes parallel to yz-plane
    b) Planes parallel to xy-plane
    c) Planes parallel to xz-plane
    d) Coaxial cylinders of increasing radius around the x-axis

  • 3. Current Electricity - Quiz


    SAMPLE QUESTIONS


    1. In the circuit shown, the internal resistance of the cell is negligible. The steady state current in the 2 Ω resistor is

    a) 0.6 A
    b) 1.2 A
    c) 0.9 A
    d) 1.5 A

    2. Thirteen resistance each of resistance R ohm are connected in the circuit as shown in the figure below. The effective resistance between A and B is

    a) R Ω
    b) 2R / 3
    c) (4R/3)Ω
    d) 2 R Ω

  • 4. Moving Charges and Magnetism - Quiz


    SAMPLE QUESTIONS


    1. The cyclotron frequency of an electron gyrating in a magnetic field of 1 T is approximately
    a) 28 MHz
    b) 280 MHz
    c) 2.8 GHz
    d) 28 GHz

    2. The maximum current that can be measured by a galvanometer of resistance 40 Ω is 10 m A . It is converted into a voltmeter that can read upto 50 V. This resistance to be connected in series with he galvanometer is…(in ohm)
    a) 2010
    b) 4050
    c) 5040
    d) 4960

  • 5. Magnetism and Matter - Quiz


    SAMPLE QUESTIONS


    1. A magnetic needle is kept in a non-uniform magnetic field. It experiences
    a) A force and a torque
    b) A force but, not a torque
    c) A torque but, not a force
    d) Neither a force nor a torque

    2. The magnetic force required to demagnetize the material is
    a) Retentivity
    b) Coercivity
    c) Energy loss
    d) Hysteresis

  • 6. Electromagnetic Induction - Quiz


    SAMPLE QUESTIONS


    1. Two circular, similar, coaxial loops carry equal currents in the same direction. If the loops are brought nearer, what will happen?
    a) Current will increase in each loop
    b) Current will decrease in each loop
    c) Current will remain same in each loop
    d) Current will increase in one and decrease in the other

    2. There is a horizontal cylindrical uniform but time-varying magnetic field increasing at a constant rate dB/dt as shown in figure. A charged particle having charge q and mass m is kept in equilibrium, at the top of a spring of spring constant K, in such a way that it is on the horizontal line passing through the centre of the magnetic field as shown in figure. The compression in the spring will be

    a) $\frac{1}{K}\left [ mg-\frac{qR^{2}}{2l}\frac{dB}{dt} \right ]$
    b) $\frac{1}{K}\left [ mg+\frac{qR^{2}}{l}\frac{dB}{dt} \right ]$
    c) $\frac{1}{K}\left [ mg+\frac{2qR^{2}}{l}\frac{dB}{dt} \right ]$
    d) $\frac{1}{K}\left [ mg+\frac{qR^{2}}{2l}\frac{dB}{dt} \right ]$

  • 7. Alternating Current - Quiz


    SAMPLE QUESTIONS


    1. In an LCR series A.C. circuit, the voltage across each of the components, L,C and R is 50V. The voltage across the LC combination will be
    a) 50 V
    b) 50 √2 V
    c) 100 V
    d) 0 V

    2. The time taken by ac of 50 Hz in reaching from zero to the maximum value is
    a) 1 x 10-2 s
    b) 2 x 10-2 s
    c) 5 x 10-3 s
    d) 5 x 10-5 s

  • 8. Electromagnetic Waves - Quiz


    SAMPLE QUESTIONS


    1. For a series LCR-circuit, the power loss at resonance is
    a) $\frac{V^{2}}{\omega L - \frac{1}{\omega C}}$
    b) i2
    c) i2R
    d) $\frac{V^{2}}{\omega C}$

    2. Velocity of light is equal to
    a) ( √ε0μ0 )
    b) ε0 / μ0
    c) (√ε0 / μ0)
    d) (√1/ε0μ0)

  • 9. Ray Optics and Optical Instruments - Quiz


    SAMPLE QUESTIONS


    1. A ray of light is incident on a medium with an angle of incidence i and refracted into a second medium with angle of refraction r. The graph of sin(i) vs sin(r) is as shown in Fig. Then, the velocity of light in the first medium in n times the velocity of light in the second medium. what should be the velue of n?

    a) $\sqrt{3}$
    b) 1/$\sqrt{3}$
    c) $\sqrt{3}$/2
    d) 2/$\sqrt{3}$

    2. In order to obtain a real image of magnification 2 using a converging lens of focal length 20 cm, where should be an object be placed?
    a) 50 cm
    b) 30 cm
    c) -50 cm
    d) -30 cm

  • 10. Wave Optics - Quiz


    SAMPLE QUESTIONS


    1. In a double - slit experiment , two parallel slits are illuminated first by light of wavelength 400 nm and then by light of unknown wavelength. The fourth - order dark fringe resulting from the known the wavelength of light falls In the same place on the screen as the second - order bright fringe from the unknown wavelength of light is
    a) 900 nm
    b) 700 nm
    c) 300 nm
    d) none of these

    2. Blue light of wavelength 480 nm is most stongly reflected off a thin film of oil on a glass slab when viewed near normal incidence . Assuming that the index of refraction of the oil is 1.2 and that of the glass is 1.6 , what is the minimum thickness of the oil film ( other than zero ) ?
    a) 100 nm
    b) 200 nm
    c) 300 nm
    d) none

  • 11. Dual Nature of Radiation and Matter - Quiz


    SAMPLE QUESTIONS


    1. Monochromatic light incident on a metal surface emits electrons with kinetic energies from zero to 2.0 eV. What is the least energy of the incident photon if the tightly bound electron needs 4.2 eV to remove ?
    a) 1.6 eV
    b) from 1.6 eV to 6.8 eV
    c) 6.8 eV
    d) More than 6.8 eV

    2. Out of a photon and an electrons, the equation E=pc is valid for
    a) both
    b) neither
    c) photon only
    d) electron only

  • 12. Nuclei - Quiz


    SAMPLE QUESTIONS


    1. At any instant , the ratio of the amounts of two radioactive substances is 2:1. IF their half-lives be, respectively12h and 16h, then after two days, what will be the ratio of the substances?
    a) 1:1
    b) 2:1
    c) 1:2
    d) 1:4

    2. Two radioactive substances A and B have decay constant 5λ and 1 λ respectively. At t=0 they have the same number of nuclei.Will be (1/e)2 after a time interval
    a) 1/4λ
    b) 4λ
    c) 2λ
    d) 1/2λ

  • 13. Semiconductor Electronics: Materials, Devices and Simple Circuit - Quiz


    SAMPLE QUESTIONS


    1. A zener diode when used as a voltage regulator is connected
    (i) in forward bias
    (ii) in reverse bias
    (iii) in parallel with load
    (iv) in series with load
    a) (i) and (ii) are correct
    b) (ii) and (iii) are correct
    c) Only (i) correct
    d) Only (iv) correct

    2. Which logic gate is represented by the following combination of logic gates?
     

    a) OR
    b) NAND
    c) AND
    d) NOR

  • 14. Communication Systems - Quiz


    SAMPLE QUESTIONS


    1. The circuit shown below acts as
     

    a) Tuned filter
    b) Low pass filter
    c) High pass filter
    d) Rectifier

    2. Which frequency range is used for optical communication?
    a) 100000 to 400000 GHz
    b) 200 KHz to 3 MHz
    c) 30000 GHz to 6000 GHz
    d) None of the above

  • 15. Atoms - Quiz


    SAMPLE QUESTIONS


    1. The ratio of the kinetic energy of then n=2 electron for the H atom to that of He+ ion is
    a) 1/4
    b) 1/2
    c) 1
    d) 2

    2. The wavelength of light emitted in the visible region by He+ ions after collisions with H atoms is
    a) 6.5 x 10-7 m
    b) 5.6 x 10-7 m
    c) 4.8 x 10-7 m
    d) 4.0 x 10-7 m

  • 16. Electric flux and Gauss Law - Quiz


    SAMPLE QUESTIONS


    1. A spherical shell of radius R = 1.5 cm has a charge q = 20μC uniformly distributed over it. The force exerted by one half over the other half is
    a) zero
    b) 10-2N
    c) 500 N
    d) 2000 N

    2. The surface density on a copper sphere is σ . The electric field strength on the surface of the sphere is
    a) σ
    b) σ/2
    c) σ/2ε0
    d) σ/ε0

  • 17. Electrical Measuring Instrument - Quiz


    SAMPLE QUESTIONS


    1. A galvanometer has a resistance of 3663Ω. A shunt S is connected across it such that 1/34 of the total current passes throug the galvanometer. The value of the shunt is
    a) 3663Ω
    b) 111Ω
    c) 107.7Ω
    d) 3555.3Ω

    2. In fig. the voltmeter and ammeter shown are ideal. Then voltmeter and ammeter readings, respectively, are

    a) 125V,3A
    b) 100V,4A
    c) 120V, 4A
    d) 120V,3A

  • 18. Heating Effect of Current - Quiz


    SAMPLE QUESTIONS


    1. The three resistances of equal values are arranged in different combinations shown below. Arrange them in increasing order of power dissipation.

    a) III < II < IV < I
    b) II < III < IV < I
    c) I < IV < III < II
    d) I < III < II < IV

    2. Four resistances carrying a current shown in figure are immersed in a box every 10min to keep the average quantity of ice in the box constant? Latent heat of ice is 80calg-1.

    a) 1.190 kg
    b) 3.20 kg
    c) 4.2 kg
    d) 0.25 kg