The bar magnet illustrated in the diagram above picks up an unmagnetised steel nail X. In turn, X picks up a similar nail Y and so on. The nail are said to be magnetised by
Aconduction
Bsingle touch
Cinduction
Ddivided touch
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Question 2
waec2003
The diagram above shows the resultant electric field pattern due to two electric point charges P and S. Which of the following statements is correct?
AP is negatively charged while S is positively charged
BP is positively charged while S is negatively charged
Cboth P and S are positively charge
Dboth P and Q are negatively charged
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Question 3
waec2003
Which of the following reactions represents nuclear fusion?
A\(^2_1H + ^2_1H \to ^3_2He + ^1_0n\)
B\(^235_92U + ^1_0n \to ^145_56Ba + ^90_36Kr \)
C\(^234_90TH \to ^0_-1n + ^3_2He + ^1_0Pa\)
D\(^238_92U \to ^4_2H \to ^3_2He + ^234_90Th\)
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Question 4
waec2003
Nuclear fission is preferred to nuclear fusion in the generation of energy because?
Avery high temperature are required for fusion
Bthe raw material of fusion are not easily obtained
Cenergy obtained from fusion is relatively smaller
Dthe by product of fusion are very dangerous
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Question 5
waec2003
The minimum energy required to remove an electron from an atom is known as
Aexcitation energy
Bionization energy
Cbinding energy
Dphoton energy
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Question 6
waec2003
A radioactive element has a decay constant of 0.077s-1, calculate its half life
A12.5s
B9.0s
C5.1s
D0.5s
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Question 7
waec2003
Which of the following statements is true of ultra violet radiations? It
Asupports the sensation of hearing
Bdoes not cause the emission of electrons from metals
Cis an electromagnetic wave
Dis not capable of causing sun burns
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Question 8
waec2003
Which of the following statements is not true of the isotopes of an element? They
Aare atoms of the same element
Bhave the same chemical properties
Chave the same atomic number
Dhave the same mass number
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Question 9
waec2003
Which of the following statements about an electromagnet is not correct?
Ait is a temporary magnet
Bits strength depends on the current
Cits stength depends on the number of turns in its coil
Dit has permanent poles
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Question 10
waec2003
The direction of induced current in a straight wire placed in magnetic field is determined by using?
AFleming's right hand rule
BMaxwell's screw rule
CFaraday's law
DLenz's law
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Question 11
waec2003
One difference between a reactance and a resistance in an alternating current circuit is
Aresistance is larger than reactance
Benergy is not diaaipated in a reactance
Cenergy is stored in a resistance but not in a reactance
Dthe current in a reactance is lower than in the resistance
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Question 12
waec2003
The maximum power dissipated by a 100\(\Omega\) resistor in a circuit is 4W. Calculate the voltage across the resistor
A10V
B20V
C25V
D400V
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Question 13
waec2003
A lamp is rated 240V 60W, calculate the resistance of its filament
A240\(\Omega\)
B360\(\Omega\)
C960\(\Omega\)
D1440\(\Omega\)
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Question 14
waec2003
A current of 10A passes through a conductor for 10s, calculate the charge flowing through the conductor
A100.0C
B10.0C
C1.0C
D0.1C
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Question 15
waec2003
Which of the following factors does not affect the the electric resistance of a wire?
Alength
Bmass
Ctemperature
Dcross sectional area
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Question 16
waec2003
Two identical cells each of e.m.f 2v and internal resistance 1.0\(\Omega\) are connected in parallel. The combination is connected to an external load of 1.5\(\Omega\). Calculate the current in the circuit
A0.57A
B1.00A
C1.14A
D2.00A
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Question 17
waec2003
A positively charged glass rod is placed by near the cap of a positively charge electroscope. The divergence of the leaf is observed to
Adecrease
Bincrease
Cremain the same
Dincrease and collapse immediately
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Question 18
waec2003
Which of the following statement about force is correct ?
Aelectrostatic, gravitational and magnetic forces are always attractive
Belectric, gravitational and magnetic field obeys inverse square law
Cfields are real but their corresponding field lines are imaginary
Dfield lines and their corresponding fields are both real
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Question 19
waec2003
Which of the following features of an electrostatic line of force is not correct?
Ait is an imaginary line which a positive charge will describe if it is free to move
Bthe tangent drawn at any point on a curved line of force shows the direction of the electric field intensity at that point
Cit is sometimes curved
Dit can cross another line of force in a region of intense electric field
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Question 20
waec2003
Which of the following instruments gives a pure note when sounded?
