Which of the following have the greatest penetrating power?
ABeta rays
BAlpha rays
CGamma rays
DElectrons
ENeutrons
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Question 12
waec1993
The potential difference between two points A and B situated at a distance d apart is V. Which of the following expresses the magnitude of the electric field intensity between the two points assuming the field is uniform?
AVd
BdV-1
CVd-1
DV2d
Ed2V
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Question 13
waec1993
A point charge of 1.0 x 10-7 C experiences force of 0.01 N in a uniform electric field. Calculate the magnitude of the strength of the field
A106 Vm-1
B105 Vm-1
C10-5 Vm-1
D102 Vm-1
E109 Vm-1
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Question 14
waec1993
In a purely resistive a.c. circuit, the current I = Io sin wt and voltage, V = Vo sin wt. Calculate the instantaneous power dissipated in the circuit in time t.
AIo Vo
B2Io Vosin wt
C(Io Vo)/2
DIo Vo sin2wt
EI2o V2o
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Question 15
waec1993
The vector diagram shown below represents the resistance R, the capacitive reactance Xc, the inductive reactance Xc and the impedance, Z in an R-L-C circuit. The current in the circuit will be maximum when
AXL = XC
BXL = XL
CR = XL
DR = X
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Question 16
waec1993
In a series R - C circuit, the resistance of the resistor is 4 Ω and capacitive reactance is 3 Ω. Calculate the impedance of the circuit
A1Ω
B4Ω
C5Ω
D7Ω
E12Ω
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Question 17
waec1993
What is the gravitational potential due to a point mass m at a distance from it? (G = gravitational constant)
A-Gm2/r2
B-Gm2/r
C–Gm/Gr2
D–Gm/r
E–Gm/2
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Question 18
waec1993
Calculate the escape velocity of a satellite launched from the earth’s surface (Take g as 10ms-2 and the radius of the earth as 6.4 x 106m)
A8.00 x 106ms-1
B1.13 x104ms-1
C3.58x102ms-1
D5.59 x10-2ms-1
E3.95x10-2ms-1
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Question 19
waec1993
A household refrigerator consumes electrical energy at the rate of 200 W. lf electricity costs 5 k per kWh, calculate the cost of operating the appliance for 30 days.
AN7.20
BN12.00
CN30.00
DN33.33
EN72.00
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Question 20
waec1993
The unit of inductance is
Afarad
Bhenry
Chertz
Dweber
Etesla
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Question 21
waec1993
Which of the following instruments can be used to compare the relative magnitude of similar charges on two given bodies?
AElectrophorus
BEbonite rod
CProof plane
DGold-leaf electroscope
ECapacitor
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Question 22
waec1993
Which of the following indicates the correct sequence of steps taken in charging a gold-leaf electroscope by induction? l. Removing the ebonite rod ll. Bringing a negatively charged ebonite rod close to the cap III. Earthing the cap IV. Disconnecting the earthing
AIII, II, I and IV
BII, I, III and IV
CIII, IV II and I
DII, III, IV and I
EIII, IV, I and II.
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Question 23
waec1993
A short chain is usually attached to the back of a petrol tanker and trailing behind it so that the
Apetrol tanker is balanced on the road
Bheat generated by friction in the engine can be conducted to the earth
Ccharges generated by friction in the tanker are conducted to the earth
Dtanker can move slowly as the chain touches the road surface
Echain can produce sound in resonance with the noise from the tanker‘s engine
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Question 24
waec1993
Which of the following is a percussion instrument?
AFlute
BOrgan
CBell
DPiano
ESonometer
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Question 25
waec1993
The quality of a note produced by a vibrating string is determined by the
Apitch of the note
Btension of the string
Cmaterial of the string
Dpresence of overtones
Ethickness of the string
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Question 26
waec1993
Which of the following is correct about light and sound waves?
ABoth of them are associated with energy transfer
BBoth of them need material media for propagation
Cthey are both longitudinal waves
Dtheir velocities in air are equal
EBoth of them can be polarized
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Question 27
waec1993
A man stands in front of a tall wall and produces a sound. If he receives the echo of the sound two seconds later, calculate his distance from the wall. (The speed of sound in air is 330ms-1)
A600m
B400m
C330m
D328m
E165m
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Question 28
waec1993
Which of the following have the longest wavelengths?
AInfra-red rays
BGamma rays
CX-rays
DUltra-violet rays
ERadio waves
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Question 29
waec1993
In a ripple tank experiment, a vibrating plate is used to generate ripples in the water. If the distance between two successive troughs is 3.5 cm and the wave travels a distance of 31.5 cm in 1.5 s, calculate the frequency of the vibrator
A3.0Hz
B6.0Hz
C12.0Hz
D27.0Hz
E73.5Hz
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Question 30
waec1993
An object is placed between two mirrors which are inclined at an angle of 120° and facing each other. Determine the number of images observed in the two mirrors
