A converging lens of focal length 5cm forms a virtual image which is 20cm from the lens. How far from the lens is the object?
A2.0cm
B4.0 cm
C6.7cm
D20.0cm
E25.0cm
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Question 2
neco2002
Which of the following is/are TRUE of nuclear fission?
I. A heavy nucleus is split into two nuclei of comparable masses.
II. Two light nuclei are joined together to form a heavier nucleus.
III. The total mass of the products is less than that of the reactants.
AI only
BII only
CIII only
DI and III only
EII and III only
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Question 3
neco2002
A transformer supplies 12V when connected to a 240V mains. If the transformer takes 0.120A from the mains when used to light a 12V, 24W lamp, what is its efficiency?
A57.20%
B66.60%
C83.30%
D92.50%
E100%
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Question 4
neco2002
Which of the following is a percussion instrument?
Abell
Bflute
Cguitar
Dpiano
Eorgan
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Question 5
neco2002
The phenomenon of photoelectric effect is NOT used in
Aautomatic doors
Bbimetallic strip thermometers
Clight meters in cameras
Dsetting off burglar alarms
Esound production from film tracks.
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Question 6
neco2002
The silvered walls of a vacuum flask minimise loss of heat due to
Aconduction and convection
Bconduction only
Cconvection and radiation
Dconvection only
Eradiation only
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Question 7
neco2002
A platinum-resistance thermometer has a resistance of 10 ω at 0°C and 18 ω at 100°C. Assuming that resistance changes uniformly with temperature, what is the resistance of the thermometer when the temperature is 45°C?
A27.8
B17.8
C13.6
D6.4
E3.6
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Question 8
neco2002
An air bubble of volume 4cm\(^3\) is formed 20m under water. What will be its volume when it rises to just below the surface of the water if the atmospheric pressure is equivalent to a height of 10m of water?
A2cm3
B4cm3
C6cm3
D8cm3
E12cm3
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Question 9
neco2002
It is NOT possible to determine exactly and simultaneously the position and momentum of a particle. This statement is known as the
ACrompton effect
Bde Broglie’s laws
CFrank-Hertz experimental law
DHeisenberg’s uncertainly principle
Ewave-particle paradox
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Question 10
neco2002
An a.c. generator can be converted into a d.c. generator by replacing
Athe slip rings with split-ring commutators
Bthe slip rings with armatures
Cthe split-rings with slip rings
Dthe split-rings with brushes
Ethe brushes with slip-ring commutators.
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Question 11
neco2002
The wavelength of a stationary wave is 36.0cm. What is the distance between a node and the next anti-node?
A6.0cm
B9.0cm
C18.0cm
D360cm
E72.0cm
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Question 12
neco2002
According to the Kinetic Theory, what does NOT occur when the temperature of a constant volume of gas is increased?
Aa decrease in the mean speed kinetic energy of the molecules
Ban increase in the mean speed of the molecules
Can increase in the momentum change at each collision.
Dan increase in the number of collisions per second
Ean increase in the pressure exerted by the gas.
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Question 13
neco2002
A body of mass M1 moving with a velocity U collides with a stationary body of mass M2 and both move with a common velocity V. If linear momentum is conserved, which expression correctly represents V?
AM1 + M2 ÷ M1U
BM2U ÷ M1 – M2
CM1U ÷ M1 – M2
DM1U ÷ M1+ M2
EM2U ÷ M1 + M2
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Question 14
neco2002
A short response time is obtained in a liquid-in-glass thermometer when the
Abulb is large and thick-walled
Bbulb is small and thick-walled
Cstem is long and thin
Dliquid is of high density and the bulb is large
Ebulb is thin-walled and the liquid is a good conductor of heat.
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Question 15
neco2002
A body is uniformly accelerated from rest. Which of the following quantities vary/varies linearly with the square of the time?
I. Displacement
II. Velocity
III. Momentum
AI only
BII only
CIII only
DI and II only
EII and Ill only
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Question 16
neco2002
An object weighing 0.60N is hung on a spiral spring and caused it to extend by 6.0cm. The object is removed and a black of wood replacing it causes the spring to extend by 10.0cm. What is the weight of the block of wood?
A0.10N
B0.36N
C0.80N
D1.00N
E3.60N
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Question 17
neco2002
When a current of 1 .0A flows in an electrolyte for 3.0h, a mass of 1 .0g is deposited. What mass will be deposited in 10.0h if a current of 3.0A flows through the electrolyte?
A30.0g
B24.0g
C10.0g
D6.0g
E0.4g
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Question 18
neco2002
Which process will increase the rate of oscillation of a pendulum?
Adecreasing the amplitude of oscillation of the pendulum
Bdecreasing the length of the pendulum
Cdecreasing the mass of the pendulum
Dincreasing the length of the pendulum
Eincreasing the mass of the pendulum.
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Question 19
neco2002
Lenz’s law of electromagnetic induction states that
Ae.m.f. is induced in a circuit whenever there is a change in the magnetic flux linked with the circuit
Bthe induced e.m.f. in a circuit is proportional to the rate of change f the number of lines of force linking the circuit
Cthe induced current in a conductor is in such a direction as to oppose the change producing it
Da force is exerted in a current-carrying conductor in a magnetic field.
Ethe induced e.m.f. is proportional to the current producing the magnetic flux.
