JAMB Physics questions

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

1. Question 261· 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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2. Question 262· 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

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3. Question 263· 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

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4. Question 264· Magnets and magnetic fields· JAMB

   At the magnetic equator, the angle of dip is

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

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5. Question 265· 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

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6. Question 266· Magnets and magnetic fields· JAMB

   The angle of dip at the magnetic equator is

   • A0°
   • B90°
   • C45°
   • D180°

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7. Question 267· Magnets and magnetic fields· JAMB

   The magnetic field round a straight current-carrying wire consists of

   • Ano field at all
   • Bstraight lines parallel to the wire
   • Cradial lines from the wire
   • Dconcentric circles round the wire

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8. Question 268· Magnets and magnetic fields· JAMB

   The best way to demagnetise a bar magnet is to

   • Akeep it with keepers
   • Bplace it in a solenoid carrying direct current
   • Cstroke it with another magnet
   • Dplace it in a solenoid carrying alternating current and slowly withdraw it

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9. Question 269· Magnets and magnetic fields· JAMB

   The angle between the geographic meridian and the magnetic meridian is called the

   • Aangle of inclination
   • Bangle of dip
   • Cangle of declination
   • Dcritical angle

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10. Question 270· Magnets and magnetic fields· JAMB

    Outside a bar magnet, magnetic field lines run from

    • Athe north pole to the south pole
    • Bthe south pole to the north pole
    • Cthe middle to the ends
    • Dnowhere; there are no field lines

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11. Question 271· Magnets and magnetic fields· JAMB

    Soft iron is used as the core of an electromagnet because it

    • Ais easily magnetised and demagnetised
    • Bkeeps its magnetism permanently
    • Cis a good conductor of heat
    • Dis very hard

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12. Question 272· Magnets and magnetic fields· JAMB

    Which group of metals is strongly magnetic?

    • Asilver, sodium and calcium
    • Bcopper, zinc and tin
    • Caluminium, lead and gold
    • Diron, nickel and cobalt

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13. Question 273· Magnets and magnetic fields· JAMB

    Soft iron keepers are placed across the poles of stored magnets in order to

    • Areverse the poles
    • Bincrease their weight
    • Cmake them magnetic
    • Dprevent self-demagnetisation

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14. Question 274· Magnets and magnetic fields· JAMB

    A neutral point in a magnetic field is a point where

    • Aonly the Earth's field acts
    • Bthe field is strongest
    • Cthe resultant magnetic field is zero
    • Dthe needle points north

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15. Question 275· Measurements and units· JAMB

    The dimensions of momentum are

    • AML²T⁻¹
    • BMLT⁻²
    • CMLT⁻¹
    • DML⁻¹T⁻¹

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16. Question 276· Measurements and units· JAMB

    Which of the following is a fundamental quantity?

    • Adensity
    • Bvelocity
    • Cforce
    • Dtime

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17. Question 277· Measurements and units· JAMB

    The watt expressed in SI base units is

    • Akg m s⁻¹
    • Bkg m s⁻²
    • Ckg m² s⁻²
    • Dkg m² s⁻³

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18. Question 278· Measurements and units· JAMB

    Which instrument would measure the diameter of a thin wire most accurately?

    • Ameasuring tape
    • Bvernier calipers
    • Cmetre rule
    • Dmicrometer screw gauge

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19. Question 279· Measurements and units· JAMB

    Which of the following quantities has the same SI unit as energy?

    • Apressure
    • Bpower
    • Cmomentum
    • Dmoment of a force

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20. Question 280· Measurements and units· JAMB

    Which of the following is NOT a fundamental SI unit?

    • Amole
    • Bkelvin
    • Campere
    • Dnewton

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