JAMB and WAEC Physics questions

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

1. Question 161· Electric cells· WAEC

   A cell of e.m.f. 9 V and internal resistance 1 Ω supplies a current of 2 A. The lost volts are

   • A7 V
   • B2 V
   • C9 V
   • D11 V

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2. Question 162· Electric cells· WAEC

   A lead-acid accumulator differs from a dry Leclanché cell in that it

   • Acan be recharged
   • Bcannot be recharged
   • Chas no electrolyte
   • Dgives no current

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3. Question 163· Electric cells· JAMB

   A cell of e.m.f. 3 V and internal resistance 1 Ω is connected to a 5 Ω resistor. Find the current.

   • A3 A
   • B0.6 A
   • C0.5 A
   • D0.75 A

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4. Question 164· Electric cells· WAEC

   A new Leclanché cell is said to have a long shelf life. Which part of a simple voltaic cell, by contrast, is eaten away even when no current is drawn?

   • Athe copper plate
   • Bthe impure zinc plate
   • Cthe dilute acid
   • Dthe connecting wire

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5. Question 165· Electric cells· JAMB

   Two cells, each of e.m.f. 1.5 V and internal resistance 0.5 Ω, are connected in series with a 4 Ω resistor. Find the current.

   • A0.33 A
   • B0.75 A
   • C0.6 A
   • D3 A

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6. Question 166· Electric cells· WAEC

   Local action in a simple cell can be reduced by

   • Ausing a stronger acid
   • Brubbing the zinc plate with mercury (amalgamation)
   • Cadding more copper
   • Dheating the cell

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7. Question 167· Electric cells· WAEC

   The positive pole of a Leclanché cell is the

   • Aammonium chloride paste
   • Bzinc case
   • Ccarbon rod
   • Dcopper wire

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8. Question 168· Electric cells· WAEC

   Two identical cells, each of e.m.f. 1.5 V, are connected in parallel. The combined e.m.f. is

   • A3.0 V
   • B1.5 V
   • C0.75 V
   • D2.25 V

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9. Question 169· Electrical energy and power· JAMB

   A 1.5 kW heater is used for 4 hours. If electricity costs ₦50 per kWh, find the cost.

   • A₦300
   • B₦75
   • C₦200
   • D₦6

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10. Question 170· Electrical energy and power· WAEC

    The fuse rating for a 920 W appliance on a 230 V supply should be about

    • A13 A
    • B1 A
    • C5 A
    • D30 A

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11. Question 171· Electrical energy and power· JAMB

    How many kilowatt-hours of energy does a 100 W bulb use in 10 hours?

    • A10 kWh
    • B1 kWh
    • C1000 kWh
    • D0.1 kWh

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12. Question 172· Electrical energy and power· JAMB

    A 13 A fuse is fitted in a 240 V circuit. What is the maximum power it allows?

    • A3,120 W
    • B18.5 W
    • C253 W
    • D31,200 W

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13. Question 173· Electrical energy and power· WAEC

    Find the resistance of a lamp rated 100 W, 240 V.

    • A2.4 Ω
    • B576 Ω
    • C24 000 Ω
    • D0.42 Ω

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14. Question 174· Electrical energy and power· JAMB

    A 12 V supply is connected across a 6 Ω resistor. Find the power.

    • A72 W
    • B24 W
    • C2 W
    • D0.5 W

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15. Question 175· Electrical energy and power· JAMB

    In a household plug, the fuse should be connected in the

    • Ainsulation
    • Bneutral wire
    • Cearth wire
    • Dlive wire

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16. Question 176· Electrical energy and power· JAMB

    An electric heater rated 2 kW is used for 3 hours. The energy consumed is:

    • A6 kWh
    • B1.5 kWh
    • C0.67 kWh
    • D5 kWh

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17. Question 177· Electrical energy and power· JAMB

    A current of 2 A flows through a 5 Ω resistor for 10 s. Find the heat produced.

    • A100 J
    • B200 J
    • C20 J
    • D50 J

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18. Question 178· Electrical energy and power· WAEC

    A fuse protects a circuit by

    • Aincreasing the voltage
    • Bstoring extra current
    • Cmelting when the current is too large
    • Dearthing the appliance

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19. Question 179· Electrical energy and power· WAEC

    A 2 kW heater is used for 3 hours. The energy used is

    • A0.67 kWh
    • B1.5 kWh
    • C5 kWh
    • D6 kWh

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20. Question 180· Electrical energy and power· JAMB

    A 60 W bulb is used on a 240 V supply. Find the current it draws.

    • A4 A
    • B0.25 A
    • C14 400 A
    • D0.5 A

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