JAMB and WAEC Physics questions

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

1. Question 461· Liquids at rest· WAEC

   A body weighs 50 N in air and 30 N when fully immersed in water. Find the upthrust on it.

   • A80 N
   • B20 N
   • C30 N
   • D50 N

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   Answer: B. 20 N

   Explanation and discussion

2. Question 462· Liquids at rest· WAEC

   A stone weighs 0.6 N in air and 0.4 N in water. Find its relative density.

   • A3
   • B1.5
   • C0.33
   • D2

   Show answer

   Answer: A. 3

   Explanation and discussion

3. Question 463· 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

   Show answer

   Answer: A. 0.6

   Explanation and discussion

4. Question 464· Liquids at rest· WAEC

   The relative density of the body above (10 N in air, 6 N in water) is

   • A2.5
   • B1.67
   • C0.6
   • D4

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   Answer: A. 2.5

   Explanation and discussion

5. Question 465· 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

   Show answer

   Answer: B. it displaces a weight of water equal to its own weight

   Explanation and discussion

6. Question 466· Liquids at rest· WAEC

   A body floats in a liquid when its weight is equal to the

   • Aupthrust on it
   • Bvolume of the liquid
   • Cmass of the container
   • Ddensity of the liquid

   Show answer

   Answer: A. upthrust on it

   Explanation and discussion

7. Question 467· Liquids at rest· WAEC

   A body floats in a liquid when

   • Aits weight equals the upthrust on it
   • Bits weight is greater than the upthrust
   • Cit is denser than the liquid
   • Dit has no weight

   Show answer

   Answer: A. its weight equals the upthrust on it

   Explanation and discussion

8. Question 468· Liquids at rest· WAEC

   A body weighs 10 N in air and 6 N when fully immersed in water. The upthrust is

   • A6 N
   • B16 N
   • C4 N
   • D10 N

   Show answer

   Answer: C. 4 N

   Explanation and discussion

9. Question 469· 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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   Answer: C. is denser

   Explanation and discussion

10. Question 470· Liquids at rest· WAEC

    The relative density of a substance of density 2,700 kg/m³ is

    • A2.7
    • B2,700
    • C0.27
    • D27

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    Answer: A. 2.7

    Explanation and discussion

11. Question 471· 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

    Show answer

    Answer: C. 20 N

    Explanation and discussion

12. Question 472· Liquids at rest· JAMB

    An object floats in a liquid when:

    • Aits density is greater than that of the liquid
    • Bthe upthrust equals its weight
    • Cthe upthrust is less than its weight
    • Dits volume is small

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    Answer: B. the upthrust equals its weight

    Explanation and discussion

13. Question 473· Liquids at rest· JAMB

    A density bottle has a mass of 20 g empty, 70 g full of water and 60 g full of a liquid. Find the relative density of the liquid.

    • A0.86
    • B1.25
    • C0.8
    • D1.17

    Show answer

    Answer: C. 0.8

    Explanation and discussion

14. Question 474· Liquids at rest· WAEC

    A hydrometer sinks deeper in a liquid that is

    • Aless dense
    • Bmore dense
    • Chotter
    • Dcoloured

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    Answer: A. less dense

    Explanation and discussion

15. Question 475· Liquids at rest· WAEC

    By the law of flotation, a floating body displaces

    • Ahalf its weight of the fluid
    • Bits own volume of the fluid
    • Cits own weight of the fluid
    • Dmore than its own weight of the fluid

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    Answer: C. its own weight of the fluid

    Explanation and discussion

16. Question 476· Magnets and magnetic fields· JAMB

    Soft iron is used in electromagnets because it

    • Akeeps its magnetism permanently
    • Bis easily magnetised and demagnetised
    • Cis non-magnetic
    • Ddoes not conduct

    Show answer

    Answer: B. is easily magnetised and demagnetised

    Explanation and discussion

17. Question 477· Magnets and magnetic fields· WAEC

    Which of the following materials is strongly attracted by a magnet?

    • AIron
    • BCopper
    • CAluminium
    • DBrass

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    Answer: A. Iron

    Explanation and discussion

18. Question 478· Magnets and magnetic fields· WAEC

    A bar magnet can be demagnetised by

    • Ahammering it while it lies east-west
    • Bstroking it with another magnet
    • Cplacing it in a solenoid carrying direct current
    • Dstoring it with keepers

    Show answer

    Answer: A. hammering it while it lies east-west

    Explanation and discussion

19. Question 479· Magnets and magnetic fields· JAMB

    At the magnetic equator, the angle of dip is

    • A90°
    • B0°
    • C45°
    • D180°

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    Answer: B. 0°

    Explanation and discussion

20. Question 480· Magnets and magnetic fields· JAMB

    The north pole of a freely suspended magnet points approximately towards the Earth's

    • Aeast
    • Bgeographic south
    • Cgeographic north
    • Dwest

    Show answer

    Answer: C. geographic north

    Explanation and discussion