Which of the following statements is true of nuclear fission?
AHeavy nuclei combine to form new element
BProtons are used in bombarding heavy nucleus
CThe sum of the masses of the products is greater than the mass of the original substance
DTwo light nuclei are made to combine to form a heavy nucleus
EVery large amount of energy is released.
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Question 62
neco2004
The temperature at which the water vapour present in the air is just enough to saturate the air is the _______ point.
Aboiling
Bcritical
Cdew
Dice
Esteam
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Question 63
neco2004
Calculate the magnitude of the electric field intensity in a vacuum at a distance of 25cm from a charge of 5 × 10-3C. Take (\(\frac{1}{4πε0} = 9\times10^9Nm^2C^{-2}\))
A7.2 × 108NC-1
B1.8 × 108NC-1
C5.6 × 108NC-1
D3.6 × 108NC-1
E1.5 × 106NC-1
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Question 64
neco2004
The time t1, t2 and t3 for 20 complete oscillations of a simple pendulum experiment are 32.0s, 34.6s and 35.5s respectively. Calculate the mean period of the pendulum.
A1.60s
B1.70s
C1.73s
D1.78s
E5.11s
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Question 65
neco2004
Which of the following is NOT an example of a percussion instrument?
ABell
BDrum
CFlute
DGong
EXylophone
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Question 66
neco2004
A mass of 5kg is suspended from the ceiling of a lift with a light inextensible string. As the lift moves upwards with an acceleration of 2ms-2, the tension in the string is [g = 10ms-2]
A25N
B40N
C50N
D60N
E70N
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Question 67
neco2004
A plane which is Inclined at an angle of 30 ° to the horizontal has a velocity ratio of
A2
B1
C0.87
D0.67
E0.5
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Question 68
neco2004
The component of a vector in a given direction is
Aequal to the magnitude of the resultant vector in that direction
Bequal to the magnitude of the resultant vector in the opposite direction
Cits effective magnitude
Dits effective value in that direction
Eits effective value in the opposite direction
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Question 69
neco2004
In which of these fields are repulsive forces NOT experienced?
I. Magnetic field
II. Gravitational field
III. Electric field
AI only
BII only
CIII only
DI and III only
EII and III only
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Question 70
neco2004
A force F is applied to a body P as shown in the diagram above. If the body moves through a distance, a, which of the following represents the work done?
AFa
BFa Cos θ
C\(\frac{Fa}{\cos \theta}\)
DFaSin θ
E\(\frac{Fa}{\sin \theta}\)
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Question 71
neco2004
A body of mass 40g loses 80J of heat energy. If the specific heat capacity of the body is 400 Jkg-1, calculate the change in temperature of the body.
A0.2K
B0.4K
C2.0K
D5.0K
E10.0K
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Question 72
neco2004
Which of the statements about prism binoculars is/are correct? They
I. are a pair of two telescopes mounted side by side
II. reduce the optical path of the light ray from the objective to the eye piece
III, present inverted and diminished image to the viewer
IV. present erect and magnified image to the viewer.
AI only
BII only
CI and II only
DI, II and IV only
EII, III and IV only
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Question 73
neco2004
How far from a hill should a boy stand to hear the echo of his clap 1 .6s later? [Speed of sound in air is 340ms-1]
A186m
B272m
C544m
D1088m
E2000m
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Question 74
neco2004
Which of the following conclusion(s) can be drawn from Newton’s second law of motion? Force is proportional to
I. the product of mass and acceleration
II. the product of mass and velocity
III. Impulse
AI only
BII only
CIII only
DII and III only
EI, II and III
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Question 75
neco2004
A voltage supply of 12V r.m.s. and frequency 90Hz is connected to a 4 ω resistor. Calculate the peak value of the current
A48.8 A
B30.0 A
C27.5 A
D4.2 A
E3.0A
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Question 76
neco2004
The general equation of a wave CANNOT be written as
Ay = A Sin [2 π (\(\frac{t}{T}\) ± Xλ)]
By = A Sin [wt ± kx]
Cy = A Sin [2 \(\frac{\pi}{\lambda}\) (vt ± x)]
Dy = A Sin [2π (ft ± \(\frac{X}{\lambda}\) )]
Ey = A Sin 2 π f(T ± \(\frac{X}{\lambda}\))]
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Question 77
neco2004
Which of these expresses the relationship between the earth’s magnetic field FE, and the field’ FB due to a magnet at neutral points? FE is
Aequal and opposite to FB
Bequal to and in the same direction with FB
Cgreater than and in the same direction with FB
Dgreater than and opposite to FB
Eless than and opposite to FB
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Question 78
neco2003
A sheet of white paper viewed through blue glass appears blue because
Ablue is a primary colour
Bthe glass absorbs all colours except the blue colour
Cthe glass reflects blue colour
Dthe paper reflects blue colour only
Ewhite light is easily absorbed by the glass
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Question 79
neco2003
Which of the following statements is NOT true?
AA lead-acid accumulator can deliver a large current because of its very large internal resistance.
BA secondary cell can be recharged.
CAs a lead-acid accumulator is being charged, the density of the acid in it increases.
DThe chemical action in a primary cell is irreversible.
EThe conventional current in a circuit rlows from the positive to the negative terminal of the battery.
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Question 80
neco2003
The volume of a given mass of gas is 40cm3 at 27° C. What is its volume at 90° C if its pressure remains constant?
