WAEC Physics questions

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

1. Question 21· Change of state· WAEC

   Evaporation differs from boiling in that evaporation

   • Aoccurs at all temperatures from the surface
   • Boccurs at a fixed temperature
   • Cproduces bubbles
   • Dneeds no heat

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2. Question 22· Conduction of electricity through liquids and gases· WAEC

   The mass of a substance liberated in electrolysis by one coulomb of charge is its

   • Avalency
   • Bmolar mass
   • Crelative atomic mass
   • Delectrochemical equivalent

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3. Question 23· Conduction of electricity through liquids and gases· WAEC

   Pure water is a poor conductor of electricity because it contains

   • Ano hydrogen
   • Bno molecules
   • Ctoo many electrons
   • Dvery few ions

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4. Question 24· Conduction of electricity through liquids and gases· WAEC

   A fluorescent tube produces light by

   • Aheating a filament
   • Ban electric discharge through a gas at low pressure
   • Cburning a gas
   • Dchemical reaction in a cell

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5. Question 25· Conduction of electricity through liquids and gases· WAEC

   During the electrolysis of copper(II) sulphate solution with copper electrodes, the mass of the cathode

   • Aincreases
   • Bdecreases
   • Cstays the same
   • Dbecomes zero

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6. Question 26· Conduction of electricity through liquids and gases· WAEC

   A current of 3 A flows for 10 minutes through an electrolyte. The electrochemical equivalent of the metal is 3 × 10⁻⁷ kg/C. Find the mass deposited.

   • A9 × 10⁻⁷ kg
   • B5.4 × 10⁻⁴ kg
   • C1.8 × 10⁻⁴ kg
   • D5.4 × 10⁻² kg

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7. Question 27· Conduction of electricity through liquids and gases· WAEC

   Electroplating a spoon with silver uses the spoon as the

   • Aelectrolyte
   • Banode
   • Ccathode
   • Dbattery

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8. Question 28· Conduction of electricity through liquids and gases· WAEC

   The mass of a substance liberated in electrolysis is proportional to the

   • Aquantity of charge passed
   • Bvoltage
   • Celectrode size
   • Dtemperature

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9. Question 29· Conduction of electricity through liquids and gases· WAEC

   A current of 2 A passes through copper sulphate solution for 30 minutes. Find the mass of copper deposited. [electrochemical equivalent of copper = 3.3 × 10⁻⁷ kg/C]

   • A3.96 × 10⁻⁵ kg
   • B5.94 × 10⁻⁴ kg
   • C1.98 × 10⁻⁵ kg
   • D1.19 × 10⁻³ kg

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10. Question 30· Conduction of electricity through liquids and gases· WAEC

    In the electrolysis of acidified water, which gas is given off at the cathode?

    • Achlorine
    • Boxygen
    • Chydrogen
    • Dnitrogen

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11. Question 31· Current electricity· WAEC

    Three 6 Ω resistors are connected in parallel. The effective resistance is

    • A3 Ω
    • B18 Ω
    • C6 Ω
    • D2 Ω

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12. Question 32· Current electricity· WAEC

    A current of 0.5 A flows for 2 minutes. How much charge passes?

    • A30 C
    • B1 C
    • C240 C
    • D60 C

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13. Question 33· Current electricity· WAEC

    Resistors of 4 Ω, 6 Ω and 10 Ω are connected in series. Find their total resistance.

    • A10 Ω
    • B1.9 Ω
    • C240 Ω
    • D20 Ω

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14. Question 34· Current electricity· WAEC

    Resistors of 2 Ω, 3 Ω and 5 Ω are connected in series. Their total resistance is

    • A10 Ω
    • B1 Ω
    • C30 Ω
    • D0.97 Ω

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15. Question 35· Current electricity· WAEC

    An ammeter is connected in a circuit

    • Aacross the cell
    • Bin parallel
    • Cin series
    • Dacross the resistor

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16. Question 36· Current electricity· WAEC

    A current of 2 A flows through a resistor of 6 Ω. The potential difference across it is

    • A3 V
    • B12 V
    • C8 V
    • D4 V

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17. Question 37· Current electricity· WAEC

    Two resistors of 4 Ω and 12 Ω are connected in parallel. Their combined resistance is

    • A3 Ω
    • B16 Ω
    • C8 Ω
    • D0.33 Ω

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18. Question 38· Current electricity· WAEC

    A wire of resistance 10 Ω carries 2 A. The p.d. across it is

    • A0.2 V
    • B5 V
    • C12 V
    • D20 V

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19. Question 39· Current electricity· WAEC

    A galvanometer is converted to an ammeter by connecting

    • Aa low resistance in parallel (a shunt)
    • Ba high resistance in series
    • Ca capacitor
    • Da diode

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20. Question 40· Current electricity· WAEC

    Ohm's law applies to a metallic conductor provided its

    • Atemperature stays constant
    • Blength changes
    • Ccurrent is a.c.
    • Dcolour is the same

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