A lamp marked 100W, 250V is lit for 10 hours. If it operates normally and 1KWh of electrical energy costs 2k, what is the cost of lighting the lamp?
A1k
B2k
C5k
D10k
E20k
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Question 13
waec1994
A particle of charge q and mass m moving with a velocity v enters a uniform magnetic field of strength B in the direction of the field. The force on the particle is
AqvB
BmqvB
CqvB/m
DmvB/q
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Question 14
waec1994
A car fuse is marked 15A and operates normally on a 12V battery. Calculate the resistance of the fuse wire
A180Ω
B27Ω
C3Ω
D1.3Ω
E0.8Ω
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Question 15
waec1994
A rectangular coil can rotate in a magnetic field. The two ends of the coil are soldered respectively to the two halves of a commutator. Two carbon brushes are made to press lightly against the commutator and when these are connected in a circuit with a battery and a rheostat, the coil rotates. This is a description of
Aa moving coil ammeter
Ba D.C generator
Ca D.C electric motor
DAn induction coil
EAn A.C generator
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Question 16
waec1994
A battery of e.m.f 10V an internal resistance 2Ω is connected to a resistance of 6Ω. Calculate the p.d
A8.75V
B7.50V
C5V
D2.50V
E1.25V
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Question 17
waec1994
Which of the following scientists postulated that moving particles exhibit wave properties?
ANiels Bohr
BErnest Rutherford
CWerner Heisenberg
DLouis de Broglie
EErwin Schroedinger
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Question 18
waec1994
Which of the following is not a part of an A.C generator?
ACarbon brushes
BSlip rings
CCommutator
DField magnet
EArmature
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Question 19
waec1994
The electrical energy supplied by a Leclanche cell is obtained from the
ANuclear energy
BMagnetic energy
CSolar energy
DChemical energy
EMechanical energy
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Question 20
waec1994
Which of the following has the shortest wavelength?
AInfrared rays
BGamma rays
CUltra violet rays
DRadio waves
EVisible light
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Question 21
waec1994
Which of the following are transverse waves? I. Ripples on water II. Sound waves in air III. Light waves from the sun?
AII only
BI only
CII and III only
DI and III only
EI, II, and III.
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Question 22
waec1994
The inability of the eye to focus near objects is known as
ALong sight
BAstigmatism
CPresbyopia
DGlaucoma
EShort sight
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Question 23
waec1994
A simple magnifying glass is used to view an object. At what distance from the lens must the object be placed so that an image 5 times the size of the object is produced 20cm from the lens?
A2cm
B4cm
C15cm
D25cm
E100cm
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Question 24
waec1994
The image of an object placed at the center of the curvature of a concave mirror is
AInverted and magnified
Bat the principal focus
Creal and diminshed
DErect and virtual
Eat the center of the curvature
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Question 25
waec1994
A hygrometer is an instrument used to measure
ADew point
BTemperature
CRelative density
DRelative humidity
EVapour pressure
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Question 26
waec1994
A steam trap is a component of apparatus used in determining the specific latent heat of vaporization of steam. In the steady state, the steam trap
Astores the steam for future use
Bprevents the steam from escaping
Censures that only dry steam gets into the calorimeter
Dallows condensed steam to go into the calorimeter
Edetermines the quantity of steam used
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Question 27
waec1994
A tap supplies water at 30°C while another supplies at 86°C. If a man wishes to bath with water at 44°C, calculate the ratio of mass of hot water to that of cold water required
A1:3
B3:1
C3:7
D7:3
E15:8
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Question 28
waec1994
The instrument used in the measurement of atmospheric pressure is?
AHydrometer
BRatemeter
CBarometer
DPhotometer
EManometer
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Question 29
waec1994
When two objects P and Q are supplied with the same quantity of heat,the temperature change in P is observed to be twice that in Q. If the masses of P and Q are the same,calculate the ratio of the specific heat capacities of P and Q
A1:1
B1:3
C1:4
D1:2
E4:1
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Question 30
waec1994
A gas occupies a certain volume at 27°C. At what temperature will its volume be three times the original volume assuming that its pressure remains constant?
