JAMB Physics questions

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

1. Question 81· Elasticity· JAMB

   A wire 2 m long with a cross-section of 1 × 10⁻⁶ m² stretches 1 mm under a load of 100 N. Find its Young's modulus.

   • A5 × 10¹⁰ Pa
   • B2 × 10⁸ Pa
   • C2 × 10¹¹ Pa
   • D1 × 10¹¹ Pa

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2. Question 82· Electric cells· JAMB

   The e.m.f. of a cell is best measured with a

   • Aammeter
   • Bpotentiometer
   • Cohmmeter
   • Dgalvanometer used alone

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3. Question 83· Electric cells· JAMB

   In a Leclanché dry cell, the positive terminal is the

   • Amanganese(IV) oxide only
   • Bzinc case
   • Cammonium chloride paste
   • Dcarbon rod

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4. Question 84· Electric cells· JAMB

   Polarisation in a simple cell is caused by

   • Aimpurities in the zinc
   • Bhydrogen bubbles collecting on the copper plate
   • Cthe acid becoming too strong
   • Dthe cell overheating

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5. Question 85· Electric cells· JAMB

   Three cells, each of e.m.f. 1.5 V and internal resistance 0.5 Ω, are connected in series. Find the total e.m.f. and internal resistance.

   • A1.5 V and 0.5 Ω
   • B4.5 V and 1.5 Ω
   • C4.5 V and 0.17 Ω
   • D1.5 V and 1.5 Ω

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6. Question 86· Electric cells· JAMB

   A cell of e.m.f. 3 V and internal resistance 1 Ω drives a current through a 5 Ω resistor. Find the terminal potential difference of the cell.

   • A3 V
   • B2.5 V
   • C0.5 V
   • D2 V

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7. Question 87· Electric cells· JAMB

   An advantage of the lead-acid accumulator over a dry cell is that it

   • Anever runs down
   • Bis lighter
   • Ccontains no liquid
   • Dcan be recharged

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8. Question 88· Electric cells· JAMB

   Connecting identical cells in parallel gives

   • Aa larger e.m.f.
   • Bthe same e.m.f. as one cell with a smaller internal resistance
   • Czero e.m.f.
   • Da larger internal resistance

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9. Question 89· Electric cells· JAMB

   Local action in a simple cell is caused by

   • Aimpurities in the zinc plate
   • Bhydrogen bubbles on the copper
   • Ctoo much acid
   • Da short circuit

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10. Question 90· Electric cells· JAMB

    A lead–acid accumulator is

    • Aa solar cell
    • Ba primary cell
    • Ca dry Leclanché cell
    • Da secondary cell that can be recharged

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11. Question 91· Electric cells· JAMB

    The electromotive force (e.m.f.) of a cell is the

    • Acurrent it produces
    • Bforce on electrons
    • Cenergy it supplies to each coulomb of charge passing through
    • Dresistance inside it

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12. Question 92· 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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13. Question 93· 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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14. Question 94· 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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15. Question 95· 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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16. Question 96· 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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17. Question 97· 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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18. Question 98· 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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19. Question 99· 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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20. Question 100· 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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