WAEC Physics questions

379 questions with answers and explanations. Tap an option to check yourself.

1. Question 101· Electrostatics· WAEC

   A gold-leaf electroscope is used to

   • Adetect electric charge
   • Bmeasure current
   • Cstore charge
   • Dmeasure resistance

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2. Question 102· Electrostatics· WAEC

   The force between two point charges is 8 N. If the distance between them is doubled, the force becomes

   • A32 N
   • B4 N
   • C16 N
   • D2 N

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3. Question 103· Electrostatics· WAEC

   Two point charges of 2 × 10⁻⁶ C each are 0.3 m apart in air. Find the force between them. [k = 9 × 10⁹ N m²/C²]

   • A1.2 N
   • B0.12 N
   • C0.4 N
   • D0.04 N

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4. Question 104· Electrostatics· WAEC

   Lightning conductors protect buildings by

   • Astoring charge
   • Bdischarging charges safely to earth
   • Cattracting rain
   • Dproducing current

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5. Question 105· Electrostatics· WAEC

   On a charged conductor, the charge is most concentrated at

   • Asharp points
   • Bflat surfaces
   • Cthe centre
   • Dhollow parts inside

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6. Question 106· Electrostatics· WAEC

   Two positively charged bodies placed close together will

   • Arepel each other
   • Battract each other
   • Cneutralise each other
   • Dnot affect each other

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7. Question 107· Elementary modern physics· WAEC

   Which radiation is stopped by a thin sheet of paper?

   • Abeta particles
   • Bgamma rays
   • Calpha particles
   • DX-rays

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8. Question 108· Elementary modern physics· WAEC

   A radioactive sample has a half-life of 5 days. What fraction of it remains after 15 days?

   • A1/8
   • B1/3
   • C1/6
   • D1/16

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9. Question 109· Elementary modern physics· WAEC

   Which radiation is the most penetrating?

   • Abeta particles
   • Balpha particles
   • Cgamma rays
   • Dcathode rays

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10. Question 110· Elementary modern physics· WAEC

    Alpha particles are

    • Ahelium nuclei
    • Belectrons
    • Cneutrons
    • Delectromagnetic waves

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11. Question 111· Elementary modern physics· WAEC

    Beta particles are

    • Ahelium nuclei
    • Bfast electrons
    • Celectromagnetic waves
    • Dneutrons

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12. Question 112· Elementary modern physics· WAEC

    Which radiation is stopped by a sheet of paper?

    • Aalpha particles
    • Bbeta particles
    • Cgamma rays
    • DX-rays

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13. Question 113· Elementary modern physics· WAEC

    The half-life of a radioactive substance is 2 days. What fraction of it remains after 6 days?

    • A1/3
    • B1/8
    • C1/6
    • D1/4

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14. Question 114· Elementary modern physics· WAEC

    In the photoelectric effect, electrons are emitted only if the light's

    • Afrequency exceeds the threshold frequency
    • Bintensity is very high
    • Cwavelength is very long
    • Dcolour is red

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15. Question 115· Elementary modern physics· WAEC

    The energy released in nuclear reactions comes from

    • Afriction
    • Bchemical bonds
    • Cthe mass defect, according to E = mc²
    • Delectric current

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16. Question 116· Elementary modern physics· WAEC

    A radioactive substance has a half-life of 4 days. The fraction left after 12 days is

    • A1/16
    • B1/4
    • C1/3
    • D1/8

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17. Question 117· Elementary modern physics· WAEC

    Light of photon energy 3.5 eV falls on a metal whose work function is 2.0 eV. Find the maximum kinetic energy of the emitted electrons.

    • A1.75 eV
    • B5.5 eV
    • C1.5 eV
    • D7.0 eV

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18. Question 118· Equilibrium of forces· WAEC

    A body is in stable equilibrium if, when slightly displaced, it

    • Arests in its new position
    • Bmoves further from its position
    • Creturns to its original position
    • Dtopples over

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19. Question 119· Equilibrium of forces· WAEC

    A uniform metre rule is balanced at its 50 cm mark. A 2 N weight hangs at the 20 cm mark. Where must a 3 N weight hang to keep it balanced?

    • A80 cm mark
    • B70 cm mark
    • C60 cm mark
    • D30 cm mark

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20. Question 120· Equilibrium of forces· WAEC

    A spanner 0.25 m long needs a turning moment of 20 Nm to loosen a nut. The force needed at its end is

    • A80 N
    • B5 N
    • C20.25 N
    • D0.0125 N

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