JAMB Physics questions

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

1. Question 241· Light: refraction· JAMB

   Find the critical angle for glass of refractive index 1.5.

   • A41.8°
   • B48.2°
   • C30°
   • D60°

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2. Question 242· Light: refraction· JAMB

   Optical fibres carry light along their length by

   • Atotal internal reflection
   • Bdiffraction
   • Cdispersion
   • Dabsorption

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3. Question 243· Light: refraction· JAMB

   When light passes from air into glass, it

   • Adoes not bend
   • Bbends away from the normal
   • Cbends towards the normal
   • Dis totally reflected

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4. Question 244· Light: refraction· JAMB

   Find the speed of light in glass of refractive index 1.5. [c = 3 × 10⁸ m/s]

   • A3 × 10⁸ m/s
   • B4.5 × 10⁸ m/s
   • C2 × 10⁸ m/s
   • D1.5 × 10⁸ m/s

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5. Question 245· Light: refraction· JAMB

   The refractive index of glass is 1.5. The speed of light in the glass is: (c = 3 × 10⁸ m/s)

   • A1.5 × 10⁸ m/s
   • B3 × 10⁸ m/s
   • C4.5 × 10⁸ m/s
   • D2 × 10⁸ m/s

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6. Question 246· Light: refraction· JAMB

   Find the speed of light in a medium of refractive index 1.33. (c = 3 × 10⁸ m/s)

   • A4.4 × 10⁸ m/s
   • B3.99 × 10⁸ m/s
   • C1.33 × 10⁸ m/s
   • D2.26 × 10⁸ m/s

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7. Question 247· Light: refraction· JAMB

   A mirage seen on a hot road is caused by

   • Adiffraction of light
   • Breflection from water on the road
   • Crefraction and total internal reflection in layers of hot air
   • Dabsorption by the road

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8. Question 248· Light: refraction· JAMB

   Find the critical angle for a medium of refractive index 2.

   • A60°
   • B30°
   • C45°
   • D90°

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9. Question 249· Light: refraction· JAMB

   Total internal reflection occurs when light goes from a denser to a less dense medium and the angle of incidence

   • Aexceeds the critical angle
   • Bis zero
   • Cis always 45°
   • Dis less than the critical angle

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10. Question 250· Liquids at rest· JAMB

    A body weighs 10 N in air and 6 N when fully immersed in water. Find the upthrust on it.

    • A10 N
    • B16 N
    • C6 N
    • D4 N

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11. Question 251· Liquids at rest· JAMB

    A hydrometer works on the principle of

    • APascal's principle
    • Bmoments
    • Cconservation of energy
    • Dflotation

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12. Question 252· Liquids at rest· JAMB

    A hydrometer floats deeper in liquid X than in water. This shows that X is

    • Aa solid
    • Bdenser than water
    • Cthe same density as water
    • Dless dense than water

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13. Question 253· Liquids at rest· JAMB

    Archimedes' principle states that a body wholly or partly immersed in a fluid

    • Afloats only if it is hollow
    • Bloses all its weight
    • Cexperiences an upthrust equal to the weight of fluid displaced
    • Dsinks if it is solid

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14. Question 254· Liquids at rest· JAMB

    A body weighs 10 N in air and 6 N when fully immersed in water. Find its relative density.

    • A4
    • B1.67
    • C0.4
    • D2.5

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15. Question 255· Liquids at rest· JAMB

    A piece of wood of density 600 kg/m³ floats in water of density 1000 kg/m³. What fraction of its volume is under the water?

    • A0.6
    • B0.4
    • C1.67
    • D0.06

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16. Question 256· Liquids at rest· JAMB

    Surface tension explains why

    • Aice floats
    • Ba ship floats
    • Ca balloon rises
    • Da dry needle can float on water

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17. Question 257· Liquids at rest· JAMB

    A block of wood of density 600 kg/m³ floats in water. What fraction of its volume is submerged?

    • A0.6
    • B0.4
    • C1.0
    • D0.06

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18. Question 258· Liquids at rest· JAMB

    A ship floats because

    • Asteel is lighter than water
    • Bit displaces a weight of water equal to its own weight
    • Cair pushes it up
    • Dit has no weight

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19. Question 259· Liquids at rest· JAMB

    A hydrometer floats higher in a liquid that

    • Ais hotter
    • Bis less dense
    • Cis denser
    • Dhas more volume

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20. Question 260· Liquids at rest· JAMB

    A block of volume 0.002 m³ is completely submerged in water of density 1000 kg/m³. Find the upthrust on it.

    • A200 N
    • B2 N
    • C20 N
    • D0.2 N

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