JAMB and WAEC Physics questions

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

1. Question 261· Elementary modern physics· JAMB

   In the photoelectric effect, the maximum kinetic energy of emitted electrons depends on the:

   • Afrequency of light
   • Bintensity of light
   • Cduration of illumination
   • Darea of the metal

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2. Question 262· Elementary modern physics· JAMB

   Isotopes of an element have the same

   • Anumber of neutrons
   • Bmass number but different atomic numbers
   • Catomic number but different mass numbers
   • Dnumber of nucleons

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3. Question 263· 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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4. Question 264· Elementary modern physics· JAMB

   When uranium-238 emits an alpha particle, the mass number of the new nucleus is

   • A242
   • B236
   • C238
   • D234

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5. Question 265· 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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6. Question 266· 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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7. Question 267· Equilibrium of forces· JAMB

   The centre of gravity of a uniform rod is at its

   • Aheavier end
   • Bmidpoint
   • Clighter end
   • Done-quarter point

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8. Question 268· 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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9. Question 269· 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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10. Question 270· Equilibrium of forces· JAMB

    A uniform beam 6 m long and weighing 200 N rests on supports at its ends A and B. A 400 N load is placed 2 m from A. Find the reaction at A.

    • A300 N
    • B233.3 N
    • C366.7 N
    • D600 N

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11. Question 271· Equilibrium of forces· JAMB

    A uniform metre rule of weight 2 N is pivoted at the 30 cm mark. What weight hung at the 10 cm mark will keep it horizontal?

    • A4 N
    • B2 N
    • C1 N
    • D6 N

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12. Question 272· Equilibrium of forces· JAMB

    Two equal and opposite parallel forces of 5 N act 0.4 m apart. Find the moment of the couple.

    • A0.08 N m
    • B12.5 N m
    • C10 N m
    • D2 N m

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13. Question 273· Equilibrium of forces· JAMB

    A uniform metre rule is balanced at the 40 cm mark when a mass of 20 g is hung at the 10 cm mark. The mass of the rule is:

    • A20 g
    • B40 g
    • C80 g
    • D60 g

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14. Question 274· 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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15. Question 275· Equilibrium of forces· WAEC

    The principle of moments states that for a body in equilibrium

    • Athe body must be moving
    • Ball forces act downwards
    • Cthe weight is zero
    • Dthe sum of clockwise moments equals the sum of anticlockwise moments

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16. Question 276· Equilibrium of forces· WAEC

    A cone resting on its flat base is in

    • Aneutral equilibrium
    • Bunstable equilibrium
    • Cstable equilibrium
    • Dno equilibrium

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17. Question 277· Equilibrium of forces· WAEC

    A uniform plank resting on a support is in equilibrium. Which statement must be true?

    • AThe support must be at the centre of the plank
    • BThe plank must be horizontal
    • CThe clockwise moments about the support equal the anticlockwise moments
    • DThe weight of the plank is zero

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18. Question 278· Equilibrium of forces· WAEC

    Find the moment of a 15 N force acting perpendicularly 0.4 m from a pivot.

    • A0.6 N m
    • B37.5 N m
    • C15.4 N m
    • D6 N m

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19. Question 279· Equilibrium of forces· WAEC

    A ball resting on a level table is in

    • Astable equilibrium
    • Bneutral equilibrium
    • Cunstable equilibrium
    • Dno equilibrium

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20. Question 280· Equilibrium of forces· WAEC

    A uniform metre rule balances at its 50 cm mark. A 30 g mass hangs at the 20 cm mark. Where must a 20 g mass hang to restore balance?

    • A80 cm mark
    • B95 cm mark
    • C70 cm mark
    • D5 cm mark

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