If the distance from a point source of sound is doubled, by what factor does the intensity decrease?
A4.00
B2.00
C0.50
D0.25
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Question 62
jamb2003
At what position will an object be placed in front of a concave mirror in order to obtain an image at infinity?
AAt the pole of the mirror
BAt the principal focus
Cat the center of the curvature
DBetween the principal focus and the center of curvature
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Question 63
jamb2003
The phenomenon where by the water droplets in the atmosphere combines with dust particles in the air to reduce visibility is
Acloud
Bmist
Chail
Dfog
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Question 64
jamb2003
If an object is placed between two parallel plane mirrors with their reflecting surfaces facing each other, how many images of the object will be formed?
AInfinite
BEight
CFour
DTwo
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Question 65
jamb2003
On a fairly cool rainy day when the temperature is 20oC, the length of a steel railroad track is 20m. What will be its length on a hot a dry day when the temperature is 40oC?
[coefficient of linear expansion of steel = 11 x 10-6K-1]
A20.013m
B20.009m
C20.004m
D20.002m
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Question 66
jamb2003
An open pipe closed at one end produces its first fundamental note. If the velocity of sound in air is P and t the length of the pipe, the frequency of the note is
A2v/t
Bv/5t
Cv/4t
Dv/2t
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Question 67
jamb2003
Thermal equilibrium between two object exist when
Athe temperature of both objects are equal
Bthe quantity of heat of both objects is the same
Cthe heat capacities of both objects are the same
Done object losses heat continuously to the other
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Question 68
jamb2003
By what factor will the size of an object placed 10cm from a convex lens be increased if the image is seen on a screen placed 25cm from the lens?
A15.0
B2.5
C1.5
D0.4
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Question 69
jamb2003
A turning fork of frequency 340Hz is vibrated just above a cylindrical tube of height 1.2m. If water is slowly poured into the tube, at what maximum height will resonance occur.
[speed of sound in air = 340ms-1]
A0.95m
B0.60m
C0.50m
D0.45m
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Question 70
jamb2003
TºC
0
5
10
15
20
40
60
S.V.P(mmHg)
4.58
6.51
8.94
12.67
17.50
55.10
149.00
The table above shows the saturation vapour pressure against temperature in a certain town. If the vapour pressure in this town at 20oC is 10mmHg, what is the relative humidity?
A170.0%
B57.0%
C17.5%
D10.0%
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Question 71
jamb2003
A satellite is in a parking orbit if its period is
Aless than the period of the earth
Bmore than the period of the earth
Cequal to the period of the earth
Dthe square of the period of the earth
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Question 72
jamb2003
A 90cm uniform lever has a load of 30N suspended at 15cm from one of its ends. If the fulcrum is at the center of gravity, the force that must be applied at its other end to keep it in horizontal equilibrium is
A15N
B20N
C30N
D60N
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Question 73
jamb2003
A piece of stone attached to one end of a string is whirled round in a horizontal circle and the string suddenly cuts. The stone will fly off in a direction
Aperpendicular to the circular path
Bparallel to the circular path
Ctangential to the circular path
Dtowards the center of the circle
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Question 74
jamb2003
The stylus of a phonograph record exerts a force of 7.7 x 10\(^{-2}\)N on a groove of radius 10\(^{-5}\)m. Compute the pressure exerted by the stylus on the groove
A2.45 x 108 Nm-2
B3.45 x 108 Nm-2
C4.90 x 108 Nm-2
D2.42 x 108 Nm-2
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Question 75
jamb2003
Water does not drop through an open umbrella of silk materials unless the inside of the umbrella is touched. This is due to
Acapilarity
Bosmotic pressure
Cviscosity
Dsurface tension
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Question 76
jamb2003
If an object just begins to slide on a surface inclined at 30o to the horizontal,the coefficient of friction is
A√3
B√3/2
C1/√2
D1/√3
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Question 77
jamb2003
A hose of cross-sectional area 0.5m2 is used to discharge water from a water tanker at a velocity of 60ms-1 in 20s into a container. If the container is filled completely, the volume of the container is
A240m3
B600m 3
C2400m 3
D6000m3
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Question 78
jamb2003
The length of piece of glass block was measured by means of a vernier calliper as shown above. The length of the glass block is
A1.63 cm
B1.64 cm
C1.65 cm
D1. 66 cm
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Question 79
jamb2003
A test tube of radius 1.0cm is loaded to 8.8g. If is placed upright in water, find the depth to which it would sink
A2.8cm
B5.2cm
C25.5cm
D28.0cm
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Question 80
jamb2003
On top of a spiral spring of the force constant 500Nm-1 is placed a mass of 5 x 10-3 kg. If the spring is compressed downwards by a length of 0.02m and then released, calculate the height to which the mass is projected
