1. Mechanics
    2. 1. Units, Dimensions and Errors
    2. Vectors and Scalars
    3. Motion in a Straight Line
    4. Projectile Motion
    5. Newton's Laws of Motion
    6. Friction
    7. Work, Energy, Power and Collision
    8. Circular motion
    9. Rotational motion
    10. Simple Harmonic Motion
    11. Gravitation
    12. Elasticity
    13. Surface Tension
    14. Fluid dynamics and Viscosity
    15. Hydrostatics
  2. Heat and Thermodynamics
    3. 16. Thermometry
    17. Thermal expansion
    18. Calorimetry, Change of State and Hygrometry
    19. Gas Laws and Kinetic theory of Gases
    20. Transmission of Heat
    21. Thermodynamics
  3. Sound and Waves
    4. 22. Wave
    23. Superposition of Waves
    24. Stationary/ Standing waves
    25. Doppler's effect and Musical sound
  4. Optics
    5. 26. Reflection of Plane and Curved Mirrors
    27. Refraction at Plane surfaces and Total internal reflection
    28. Refraction through prism and Dispersion of Light
    29. Refraction through Lenses
    30. Chromatic abberation in Lenses, Optical instruments and Human eye
    31. Velocity of Light
    32. Photometry
    33. Wave nature of Light
  5. Electrostatics
    6. 34. Charge and Force
    35. Electric Field and Potential
    36. Capacitance
  6. Electrodynamics
    7. 37. Electric current
    38. Heating Effect of Current
    39. Thermoelectricity
    40. Chemical effect of Current
    41. Meters
  7. Electromagnetism
    8. 42. Properties of Magnets
    43. Magnetic effects of Current
    44. Electromagnetic induction
    45. Alternating current
  8. Modern Physics
    9. 46. Cathode rays, Positive rays and Electrons
    47. Photoelectric effect
    48. X-rays
    49. Atomic structure and Spectrum
    50. Radioactivity
    51. Nuclear physics
    52. Semiconductor and Semiconductor devices
    53. Diode and Triode valves
    54. Logic gates
    55. Relativity and Universe
    56. Particle physics
Electrostatics
34. Charge and Force
1. A positively charged particle moving east enters a region of uniform magnetic field directed vertically upwards. The particle will:

[IOM 2013]

  • Deflect vertically upwards
  • Move in a circular orbit with increased speed
  • Move in a circular orbit with constant speed
  • Continue moving east
2. A moving charged particle experiences force in:

[IOM 2012]

  • All charged particles deflect in magnetic field
  • No charged particles deflect
  • Charged particles move along magnetic field
  • Charged particles move inclined to magnetic field
3. Two ebonite rods (radii 1.5cm and 2cm) rubbed together will:

[IOM 2010]

  • Both remain neutral
  • A becomes positively charged
  • A becomes negatively charged
  • Both acquire similar charges
4. A thin water stream is attracted by a rod placed near it. The rod is:

[IOM 2010]

  • South pole of magnet
  • Charged with static electricity
  • North pole of magnet
  • Non-magnetic substance
5. Neutral metal gains 32μC charge when rubbed with wool. Electron transfer count:

[MOE 2068]

  • 1.25×1011
  • 2.5×1012
  • 2×1014
  • 5×1013
6. Force between electron and proton at 0.53Å separation:

[MOE 2068]

  • 8.2×10-6 N
  • 8.2×10-4 N
  • 8.2×10-5 N
  • 8.2×10-3 N
7. Ratio of electric to gravitational force between electrons:

[MOE 2010]

  • 1042
  • 1039
  • 1036
  • 109
8. Force between two 1μC charges at 1m separation:

[MOE 2009]

  • 9×10-4 N
  • 9×10-3 N
  • 9×10-5 N
  • 9×10-2 N
9. Positive charge Q released between two fixed -q charges at (0,a) and (0,-a):

[BP 2010]

  • Moves to infinity
  • Stops at origin
  • Executes SHM
  • Oscillates non-SHM
10. Glass rod becomes positive when rubbed with silk due to:

[BP 2010]

  • Electron addition
  • Electron removal
  • Proton addition
  • Proton removal
11. Work done moving charge on equipotential surface:

[KU 2011]

  • Zero
  • q/(4πε0r)
  • q2/(4πε0r)
  • q2/r
12. Specific charge of electron:

[BP 2013]

  • 1.76×10-11 C/kg
  • 1.76×1011 C/kg
  • 6.023×10-23 C
  • 1.6×10-19 C
13. Charged sphere (radius a, charge Q) contacts uncharged sphere (radius b). Remaining charge on A:

[IE 2011]

  • aQ/b
  • bQ/a
  • aQ/(a+b)
  • bQ/(a+b)
14. Distance between plates with E=106 V/m and ΔV=103 V:

[KU 2010]

  • 10-3 m
  • 109 m
  • 1015 m
  • 1039 m
15. Equipotential surface for point charge at large distance appears:

[IE-05]

  • Plane
  • Circular
  • Elliptical
  • Spherical
16. Surface charge density for 100V sphere (r=2cm):

[IE-06]

  • 4.4×10-8 C/m2
  • 4.4×10-7 C/m2
  • 2.4×10-6 C/m2
  • 2.4×10-5 C/m2
17. Potential at center of cube with identical charges at corners:

[]

  • 4q/(√3πε0a)
  • 2q/(√3πε0a)
  • √3q/(πε0a)
  • Zero
18. Correct statement about matter waves:

[BPKIHS-94]

  • Only charged particles have matter waves
  • Only subatomic particles have matter waves
  • All moving particles have matter waves
  • No particles have matter waves
19. Electric field inside uniformly charged sphere:

[BPKIHS-94]

  • Constant
  • Decreases
  • Increases
  • Zero
20. Ball 1's charge based on attraction/repulsion patterns:

[BPKIHS-07]

  • Positive
  • Negative
  • Neutral
  • Metallic
21. Characteristic of electric field lines:

[IE-02]

  • Negative to positive
  • Denser where E is weaker
  • Physically exist
  • Same for all conductors
22. Charge on inner sphere when connected to outer sphere (Q and q):

[IE-03]

  • Zero
  • Q-q
  • Q
  • Q+q
23. Correct statement about electrification:

[IOM 2003]

  • Glass becomes -ve with metal
  • Glass becomes +ve with flannel
  • Glass becomes +ve with ebonite
  • Glass becomes -ve with amber
24. Gold leaf electroscope measures:

[IOM 2002]

  • Charge
  • Potential
  • Energy
  • None
25. Sparking when removing wool sweater over nylon shirt is due to:

[IOM 1999]

  • Static electricity
  • Current electricity
  • None
  • Both
26. Equilibrium condition for charge q between two Q charges:

[MOE]

  • -Q/2
  • -Q/4
  • -4Q
  • Q/2
27. Position for +Q between +q and +nq to experience zero force:

[]

  • r/(1+1/√n)
  • r²/(1+1/√n)
  • r/(1+√n)
  • r/√(1+n)
28. Force ratio between (+10μC, -20μC) and after contact:

[]

  • -8:1
  • 8:1
  • 16:1
  • -16:1
29. Maximum force when dividing Q=120μC into two parts:

[]

  • 60μC
  • 40μC
  • 30μC
  • 10μC
30. Percentage force change when distance increases 25%:

[]

  • 36% decrease
  • 56% decrease
  • 65% decrease
  • 50% decrease
31. New Coulomb force when half-space filled with εr=4:

[]

  • F
  • 3F/8
  • 4F/9
  • 2F/9
32. Force ratio between +1μC and +3μC charges:

[]

  • 1:3
  • 3:1
  • 1:25
  • 1:1
33. Force on q2 due to q1 when q3 is introduced:

[]

  • Increases
  • Decreases
  • Remains same
  • Depends on signs
34. Net force on sphere C after touching A and B (initial force 3×10-5 N):

[]

  • 1×10-5 N
  • 2×10-5 N
  • 1.5×10-5 N
  • 3×10-5 N
35. Electrons transferred for -4×10-7 C charge:

[]

  • 1.5×1012
  • 2.5×1012
  • 2.5×1013
  • 3.5×1013
36. Charge on 10cm sphere after connecting to 15cm sphere (150V and 100V):

[]

  • 2 e.s.u.
  • 6 e.s.u.
  • 4 e.s.u.
  • 8 e.s.u.
37. Charges on spheres A and B when ebonite rod brought near A:

[]

  • A: +ve, B: -ve
  • A: -ve, B: +ve
  • Both +ve
  • Both -ve
38. Net force on charge in equilateral triangle (each pair force = F):

[]

  • √2 F
  • √3 F
  • 2 F
  • 3 F
39. New repulsion force after touching and redistributing charges:

[]

  • F
  • F/8
  • 5F/4
  • 3F/8
40. Electric field E compared to measured F/q0:

[IE]

  • E > F/q0
  • E = F/q0
  • E < F/q0
  • Cannot estimate
41. Distance for same force in dielectric medium (K):

[]

  • r
  • r/K
  • r/√K
  • √K×r
42. Closest approach distance when initial speed doubles:

[]

  • r
  • r/2
  • r/4
  • r/8
43. Force ratio between charges at constant potential in air vs dielectric (K):

[]

  • 1:K
  • K:1
  • 1:K²
  • K²:1
44. Correct statement about molecular potential vs distance graph:

[KU 2015]

  • Equilibrium at P
  • Repulsive at r>r0
  • Attractive at r0
  • Both (a) and (c)
45. Smaller charge when two spheres (total 40μC) repel with 2.0N at 50cm:

[KU 2015]

  • 1.4μC
  • 1.1μC
  • 2.0μC
  • 3.3μC