WAEC Physics questions

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

1. Question 1· Capacitors· WAEC

   The unit of capacitance is the

   • Afarad
   • Bcoulomb
   • Chenry
   • Dvolt

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2. Question 2· Capacitors· WAEC

   Capacitors of 3 μF and 6 μF are connected in series. Find the combined capacitance.

   • A2 μF
   • B9 μF
   • C4.5 μF
   • D18 μF

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3. Question 3· Capacitors· WAEC

   A charged capacitor stores energy in

   • Aits connecting wires
   • Bthe electric field between its plates
   • Ca magnetic field
   • Dthe battery

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4. Question 4· Capacitors· WAEC

   A 10 μF capacitor charged to 100 V stores energy of

   • A0.5 J
   • B0.05 J
   • C1,000 J
   • D0.1 J

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5. Question 5· Capacitors· WAEC

   The charge on a 5 μF capacitor at 20 V is

   • A25 C
   • B4 × 10⁻⁶ C
   • C100 C
   • D1 × 10⁻⁴ C

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6. Question 6· Capacitors· WAEC

   Two 4 μF capacitors in series have an effective capacitance of

   • A2 μF
   • B8 μF
   • C4 μF
   • D16 μF

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7. Question 7· Capacitors· WAEC

   Capacitors of 4 μF and 12 μF are connected in series. Find their combined capacitance.

   • A3 μF
   • B16 μF
   • C8 μF
   • D48 μF

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8. Question 8· Capacitors· WAEC

   A 4 μF capacitor is charged to 100 V. How much energy does it store?

   • A2 × 10⁻⁴ J
   • B0.04 J
   • C200 J
   • D0.02 J

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9. Question 9· Capacitors· WAEC

   A capacitor stores 60 μC when charged to 12 V. Find its capacitance.

   • A72 μF
   • B720 μF
   • C0.2 μF
   • D5 μF

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10. Question 10· Capacitors· WAEC

    A capacitor stores a charge of 0.002 C at 50 V. Find its capacitance.

    • A2.5 × 10⁴ F
    • B0.1 F
    • C4 × 10⁻⁵ F
    • D4 × 10⁻³ F

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11. Question 11· Change of state· WAEC

    The flat part of a cooling curve shows that the substance is

    • Againing heat
    • Bcooling fastest
    • Cat room temperature
    • Dchanging state

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12. Question 12· Change of state· WAEC

    While water is boiling its temperature stays constant because the heat supplied

    • Ais used to overcome the forces between molecules
    • Bescapes to the surroundings
    • Craises the kinetic energy of the molecules
    • Dis changed into light

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13. Question 13· Change of state· WAEC

    How much heat is needed to melt 0.2 kg of ice at 0 °C? [specific latent heat of fusion = 3.36 × 10⁵ J/kg]

    • A6.72 × 10⁴ J
    • B3.36 × 10⁴ J
    • C1.68 × 10⁶ J
    • D6.72 × 10⁵ J

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14. Question 14· Change of state· WAEC

    Boiling differs from evaporation because boiling

    • Atakes place at all temperatures
    • Btakes place at a definite temperature throughout the liquid
    • Coccurs only at the surface
    • Dproduces no vapour

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15. Question 15· Change of state· WAEC

    Food cooks faster in a pressure cooker because

    • Athe pressure lowers the boiling point
    • Bthe higher pressure raises the boiling point of water
    • Csteam escapes quickly
    • Dless heat is needed to melt it

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16. Question 16· Change of state· WAEC

    Evaporation differs from boiling because evaporation

    • Aoccurs throughout the liquid
    • Btakes place only at 100 °C
    • Ctakes place at all temperatures from the surface of the liquid
    • Dneeds no heat

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17. Question 17· Change of state· WAEC

    Heat required to melt 0.5 kg of ice at 0 °C (latent heat 3.4 × 10⁵ J/kg) is

    • A6.8 × 10⁵ J
    • B1.7 × 10⁵ J
    • C3.4 × 10⁵ J
    • D3.4 × 10⁴ J

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18. Question 18· Change of state· WAEC

    Find the heat needed to change 2 kg of water at 100 °C to steam. (Specific latent heat = 2.26 × 10⁶ J/kg)

    • A4.52 × 10⁶ J
    • B2.26 × 10⁶ J
    • C1.13 × 10⁶ J
    • D9.04 × 10⁶ J

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19. Question 19· Change of state· WAEC

    The heat absorbed when a solid changes to a liquid without a change in temperature is called

    • Alatent heat of vaporisation
    • Blatent heat of fusion
    • Cspecific heat capacity
    • Dheat of combustion

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20. Question 20· Change of state· WAEC

    The change of a substance directly from solid to vapour is called

    • Acondensation
    • Bevaporation
    • Csublimation
    • Dmelting

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