JAMB Physics questions

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

1. Question 141· Elementary modern physics· JAMB

   How many neutrons are in the nucleus of ¹⁴₆C?

   • A6
   • B8
   • C14
   • D20

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2. Question 142· Elementary modern physics· JAMB

   A radioactive sample has a half-life of 4 days. The fraction remaining after 12 days is:

   • A1/2
   • B1/4
   • C1/3
   • D1/8

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3. Question 143· Elementary modern physics· JAMB

   When a nucleus emits a beta particle, its atomic number

   • Adecreases by 2
   • Bdecreases by 1
   • Cincreases by 1
   • Dstays the same

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4. Question 144· Elementary modern physics· JAMB

   Which radiation is the least penetrating?

   • AX-rays
   • Bbeta particles
   • Cgamma rays
   • Dalpha particles

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5. Question 145· Elementary modern physics· JAMB

   Find the energy of a photon of frequency 5 × 10¹⁴ Hz. (h = 6.6 × 10⁻³⁴ J s)

   • A1.32 × 10⁻⁴⁸ J
   • B3.3 × 10⁻¹⁹ J
   • C6.6 × 10⁻²⁰ J
   • D3.3 × 10⁻¹⁴ J

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6. Question 146· Elementary modern physics· JAMB

   A beta particle is

   • Aa fast-moving electron
   • Ba helium nucleus
   • Ca photon
   • Da neutron

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7. Question 147· 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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8. Question 148· 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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9. Question 149· 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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10. Question 150· 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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11. Question 151· 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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12. Question 152· 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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13. Question 153· 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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14. Question 154· 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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15. Question 155· Equilibrium of forces· JAMB

    The centre of gravity of a uniform triangular sheet is at the

    • Apoint where its medians meet
    • Bmidpoint of its base
    • Capex
    • Dcentre of its inscribed circle

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16. Question 156· Equilibrium of forces· JAMB

    When three coplanar forces keep a body in equilibrium, they can be represented by

    • Athe radius of a circle
    • Ba straight line
    • Ctwo parallel lines
    • Dthe three sides of a triangle taken in order

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17. Question 157· Equilibrium of forces· JAMB

    A uniform metre rule balances at the 50 cm mark. A 30 N weight hangs at the 20 cm mark. What weight at the 70 cm mark keeps the rule balanced?

    • A60 N
    • B30 N
    • C20 N
    • D45 N

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18. Question 158· Equilibrium of forces· JAMB

    

    A uniform metre rule is balanced horizontally on a pivot at its 50 cm mark by the two weights shown. Find W.

    • A6 N
    • B3 N
    • C12 N
    • D8 N

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19. Question 159· Equilibrium of forces· JAMB

    A body acted on by parallel forces is in equilibrium when

    • Aonly the sum of the moments is zero
    • Bonly the sum of the forces is zero
    • Cthe sum of the forces and the sum of their moments are both zero
    • Dall the forces are equal

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20. Question 160· Equilibrium of forces· JAMB

    A body is in stable equilibrium if, when slightly displaced, its centre of gravity

    • Afalls
    • Brises
    • Cstays at the same level
    • Dmoves outside its base

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