The magnification produced with a converging lens is 5. If the object is a square wire gauze of side 2cm, calculate the area of the image
A100\(cm^2\)
B40\(cm^2\)
C20\(cm^2\)
D10\(cm^2\)
E4\(cm^3\)
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Question 692
waec1997
Which of the following is not true of the similarities between a camera and the human eye?
ABoth the camera and the human eye have light proof interiors
BBoth the camera and the human eye have light sensitive screens
CInverted images are formed on the screen in both
DThe distance between the lens and the screen is fixed in both
EThe amount of light entering both the eye and the camera can be adjusted
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Question 693
waec1997
The invisible part of the spectrum of a white light consists of the following colors
ARed, orange and yellow only
BInfra-red, ultraviolet and blue only
CIndigo and green only
DViolet and red only
EUltra violet and infra-red only
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Question 694
waec1997
An alternating current with a peak value of 5A passes through a resistor of resistance 10Ω. Calculate the rate at which energy is dissipated in the resistor
A250W
B125W
C50W
D35.4W
E12.5W
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Question 695
waec1997
A progressive wave has a wavelength of 50cm. calculate the phase difference between two points at a distance of 20cm apart.
A10/3π
B5/2 π
C4/5 π
D2/3 π
Eπ/3
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Question 696
waec1997
Which of the following statements is not correct?
AThe pitch of a note depends on the frequency of the vibrating source
BThe loudness of a note depends on its intensity
CThe velocity of sound in air does not depend on the intensity of the note producing it
DThe overtones present in a note determine its quality
EWind speed effects on the speed of sound in air
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Question 697
waec1997
A pipe open at both ends, produces a fundamental note. If the velocity of sound in air is V and L the length of the pipe, which of the following expresses the frequency of the note? Neglect end correction
A2V/L
BV/2L
CV/3L
DV/4L
EV/5L
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Question 698
waec1997
When a resistor of resistance R is connected across a cell, the terminal p.d of the cell is reduced to three quarters of its e.m.f. The internal resistance of the cell is expressed as
AR/4
BR/3
CR/2
D3R/4
E3R
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Question 699
waec1997
Two identical waves traveling in the same direction are superimposed. What should be the phase difference between the waves for maximum destructive interference to occur?
A20°
B45°
C180°
D225°
E270°
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Question 700
waec1997
In a photocell, light energy is converted to
AElectrical energy
BChemical energy
CHeat energy
DMechanical energy
EKinetic energy
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Question 701
waec1997
The current in the primary coil of a transformer is 2.5A. If the coil has 50 turns and the secondary250 turns, calculate the current in the secondary coil. Neglect energy losses in the transformer
A0.2A
B0.5A
C2.5A
D5A
E12.5A
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Question 702
waec1997
The relationship between the directions of magnetic field, the current-carrying wire in the field is easily remembered using
AOctet rule
BRight hand grip rule
CMaxwell’s screw rule
DAmpere’s swimming rule
EFleming’s left hand rule
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Question 703
waec1997
Lenz’s law of electromagnetic induction is essentially a statement of the
AInverse square law of gravitation
BInverse square law of magnetism
CInverse square law of electrostatics
DLaw of conservation of momentum
ELaw of conservation of energy
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Question 704
waec1997
The odor of a leaking gas is perceived at a distance from the source. This is made possible by the process of
ASublimation
BDiffusion
COsmosis
DEvaporation
ECapillarity
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Question 705
waec1997
The half-life of a radioactive material is 6hrs. What quantity of 1kg of the material would decay in 24 hours?
A\(\frac{15}{16}\)kg
B\(\frac{1}{2}\)kg
C\(\frac{1}{4}\)kg
D\(\frac{1}{8}\)kg
E\(\frac{1}{6}\)kg
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Question 706
waec1997
When a paint brush is removed from clean water, the bristles of the brush are pulled together because of
AThe viscosity of the surrounding air
BThe low density of water
CSurface tension forces
DThe weight of the brush bristles
EThe mass of the brush bristles
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Question 707
waec1997
Which of the following statements is not true of nuclear fission?
AMother nucleus is broken into two daughter nuclei of roughly equal parts
BNeutron is normally used in bombarding heavy nucleus
CTwo light nuclei are made to combine to form a heavy nucleus
DVery enormous energy is released
EThere is an apparent loss of mass
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Question 708
waec1997
The ratio of tensile stress to tensile strain is known as
AModulus of integrity
BModulus of elasticity
CShear modulus
DBulk modulus
EYoung’s modulus
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Question 709
waec1997
Which of the following is not correct about the Rutherford’s model of an atom?
AThe mass of an atom is concentrated around the nucleus
BThe nucleus of an atom is positively charged
CThe nucleus is surrounded by the electron cloud
DThe model is applicable to atoms with only one electron in the outer shell
EThe diameter of the nucleus is \(10^{-15}m\)
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Question 710
waec1997
Which of the following statements about kinetic theory of matter is not correct?
AThe molecules of matter are always in motion
BWhen a body is heated the average kinetic energy of its molecules decreases
CMolecules of a liquid move more freely than those of a solid
DMatter is made up of very tiny particles called molecules
EThe molecules of a gas move more freely than those of a liquid
