Which of the following statements is/are correct in any machine?
I. The velocity ratio is usually greater than the mechanical advantage.
II. Efficiency work inputwork outputIII. The velocity ratio is independent of friction.
AI only
BIII only
CI and II only
DI and III only
EII and III only
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Question 12
neco2005
An object of mass 5.0 cg moving with a velocity of 12ms-1 due north hits a stationary body of mass 7.0kg. If they stick together after collision and move with velocity V due north, calculate the magnitude of V.
A12ms-1
B7ms-1
C6ms-1
D5ms-1
E4ms-1
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Question 13
neco2005
Which of the following is NOT a component of an a.c. generator?
AArmature
BCarbon brushes
CMagnet
DSlip ring
ESplit rings
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Question 14
neco2005
Which of the following is a non-renewable energy source?
ACoal
BHydro
COcean waves
DSolar
ETides
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Question 15
neco2005
The escape velocity of an object from the gravitational field of a planet
I. Increases with the mass of the object
II. Increases with the mass of the planet
III. Is smaller on the moon than on the earth. Which of the above statements is/are correct?
AI only
BII only
CI and II only
DII and III only
EI, II and III
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Question 16
neco2005
The mercury column in a simple mercury barometer is of height 5m above the mercury in a reservoir. If the tube is replaced with one whose radius is twice that of the first tube, what will be the height of the mercury column in the new tube?
A2.5m
B5.0m
C7.5m
D10.0m
E20.0m
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Question 17
neco2005
Calculate the peak voltage that could be obtained from a 220 V\(_{r.m.s}\)main supply.
A70.7V
B110.0V
C155.6V
D311.1V
E440.0V
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Question 18
neco2005
Which of the following pairs is an example of translucent bodies?
ACardboard and moon
BClear water and glass
CFrosted glass and waxed paper
DOiled paper and brick
EWood and metal sheet
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Question 19
neco2005
The length of a simple pendulum is increased by a factor of four. By what factor is its period Increased?
A0.25
B0.5
C1.66
D2
E4
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Question 20
neco2005
When some ice cubes are added to a glass of warm water, the glass is cooled by a process of
Aconduction only
Bconvection only
Cconduction and convection
Dconduction and radiation
Eradiation only
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Question 21
neco2005
Mercury does NOT wet glass because
Aglass is an amorphous substance
Bthe adhesive force is greater than the cohesive force
Cthe cohesive force is greater than the adhesive force.
Dmercury has very high thermal conductivity
Emercury is opaque.
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Question 22
neco2005
When a yellow card is viewed in blue light, It will appear
Ablack
Borange
Cpurple
Dred
Ewhite
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Question 23
neco2005
Two metals A and B lose the same quantity of heat when their temperatures drop from 20°C to 15°C. If the specific heat Capacity of A Ii thrice that of B, calculate the ratio of the mass of A to that of B.
A3:01
B4:03
C3:04
D1:02
E1:03
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Question 24
neco2005
A voltage of 240V is connected to the primary coil of a transformer, the rating of the primary turns to the secondary turns if the voltage available at the secondary coil is 15V
A0.06
B0.9
C1.6
D16
E36
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Question 25
neco2005
Calculate the magnitude of the force due to a magnetic field of 0.40T on an electron moving perpendicular to the field with a speed of 4.00 × 106ms-1 (e 1.60 × 10-19C]
A6.40 × -10
B6.40× 10-13N
C2.56 × 10-13N
D1.60 × 10-12N
E2.30 × 10-11N
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Question 26
neco2005
A stone of mass 0.7 kg is projected vertically upward with a speed of 5 ms-1. Calculate the maximum height reached. [g =10ms-2]
A1.25m
B1.50m
C2.50m
D3.75m
E5.00Nm
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Question 27
neco2005
A projectile is projected with an initial velocity u, at an angle θ to the horizontal. The maximum height attained is.
AU2 sin \(\frac{\theta}{g}\)
B2U2 sin2 \(\frac{\theta}{g}\)
CU sin2 \(\frac{\theta}{g}\)
DU2 sin2\(\frac{\theta}{2g}\)
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Question 28
neco2005
Which of the following is a desirable property of a fuse Wire?
AHigh expansively
BHigh thermal conductivity
CLow density
DLow electrical resistivity
ELow melting point
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Question 29
neco2005
In which of the following is the expansion of solids a disadvantage?
AElectric iron
BFire alarm
CThe balance wheel of a watch
DThe bimetallic thermometer
EThe fitting of wheels in rims
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Question 30
neco2005
A 12V battery supplies a current of 0.4A to a lamp. Calculate the resistance of the lamp.
