The electromagnetic waves that are sensitive to temperature changes are
AX-rays
BGamma-rays
CUltra-violet rays
DInfra-red rays
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Question 12
jamb1997
Light of velocity 3 x 108ms-1 is incident on a material of reflective of index n. If the velocity of light is reduced to 2.4 x 108ms-1 in the material, what is n?
A2.33
B2.25
C1.33
D1.25
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Question 13
jamb1997
A boy on looking into a mirror observed that his face appeared to have grown bigger. The boy must have been looking at a
Aconvex mirror with his face at the focus
Bconcave mirror with his face between the focus and the mirror
Cconcave mirror with his face at the focus
Dconvex mirror with his face between the focus and the mirror
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Question 14
jamb1997
If the load at the end of a sonometer wire is immersed in a bucket of water, the original fundamental frequency of the wire could be restored by
Adecrease the length of the wire
Bincreasing the length of the wire
Cincreasing the mass per unit length of the wire
Dchanging the temperature of the wire
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Question 15
jamb1997
The colours seen in the thin films of oil on the road and in soap bubbles are due to
Areflection
Binterference
Cdiffraction
Dpolarization
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Question 16
jamb1997
Under constant tension and constant mass per unit length, the note produced by a plucked string is 500Hz when the length of the string is 0.90m. At what length is the frequency 150Hz?
A3m
B4m
C5m
D6m
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Question 17
jamb1997
Ripples on water and light waves are similar because both?
Ahave the same frequency
Bcan be refracted and diffracted
Care longitudinal waves
Dhave the same velocity
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Question 18
jamb1997
What happens when a gas expands at constant temperature?
Aits pressure decreases
Bthe total momentum of its molecules remains constant
Cits pressure decreases and the total momentum of its moleculees remains constant
Dits pressure decreses and the total kinetic energy of its molecule decreases
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Question 19
jamb1997
A mass of a liquid at 30oC is mixed with a mass of the same liquid at 70oC and the temperature of the mixture is 45oC. Find the ratio of the mass of the cold liquid to the mass of the other liquid.
A3 : 5
B5 : 3
C3 : 7
D7 : 3
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Question 20
jamb1997
A heating coil rated at 100W is used to boil off 0.5kg of boiling water. The time taken to boil off the water is [specific latent heat of vaporization of water = 2.3 x 106Jkg-1]
A1.15 x 109 s
B1.15 x 107 s
C1.15 x 105 s
D1.15 x 104 s
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Question 21
jamb1997
What happens when a, certain quantity of pure ice is completely changed to water at 0oC?
Alatent heat is absorbed, the mass remains constant, and the volume decreases
Blatent heat is given out, the mass remains constant and the volume decreases
Clatent heat is given out, the mass increases and the volume remains constant
Dlatent heat is absorbed, the mass decreases and the volume increases
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Question 22
jamb1997
Before starting a journey, the tyre pressure of a car was 3 x 105Nm-2 at 27oC. At the end of the journey, the pressure rose to 4 x 105Nm-2. Calculate the temperature of the tyre after the journey, assuming the volume is constant
A400oC
B300oC
C273oC
D127oC
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Question 23
jamb1997
Equal masses of copper and rubber are raised to the same temperature. After sometimes, the copper was observed to be at a lower temperature because
Athe specific heat capacity of copper is lower than that of rubber
Bcopper expands more than rubber
Cthe specific heat capacity of rubber is lower than that of copper
Drubber expands more than copper
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Question 24
jamb1997
The length of mercury thread when it is at 0°C, 100°C and at an unknown temperature \(\theta\) is 25mm, 225mm and 175mm respectively. The value of \(\theta\) is
A85.0oC
B80.0oC
C75.0oC
D70.0oC
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Question 25
jamb1997
An empty 60 litre petrol tank has a mass of 10kg. Its mass when full of fuel of relative density 0.72 is
A7.2kg
B33.2kg
C43.2kg
D53.2kg
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Question 26
jamb1997
A liquid of mass 1.0 x 103kg fills a rectangular tank of length 2.5m and width 2.0m. If the tank is 4m high, what is the pressure at the middle of the tank?[g = 10ms-2]
A1.0 x 104Nm-2
B2.0 x 103Nm-2
C1.5 x 103Nm-2
D1.0 x 103Nm-2
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Question 27
jamb1997
A piece of wire gauze can be made to lie on water because
Athe wire guaze is less dense than water
Bthe water molecules repels the wire guaze upwards
Cthe water surface has the effect of an elastic thin skin
Dof the cohensive forces between the water and the wire guaze molecules
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Question 28
jamb1997
A cube of sides 0.1m hangs freely from a string. What is the upthrust on the cube when totally immersed in water? [density of water is 1000kgm-2, g = 10ms-2]
A1000 N
B700 N
C110 N
D10 N
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Question 29
jamb1997
A load of 20N on a wire of cross-sectional area 8 x 10-7m2, produces an extension of 10m2. calculate Young's modulus for the material of the wire if its length is 3m
A7.0 x 1011Nm-2
B7.5 x 1011Nm-2
C8.5 x 1011Nm-2
D9.0 x 1011Nm-2
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Question 30
jamb1997
An electric water pump rate 1.5 kW, lifts 200kg of water through a vertical height of 6 meters in 10 seconds. What is the efficiency of the pump? [g = 10ms-2, neglecting air resistance]
