Q8005.A current of $0.5 \mathrm{A}$ flowing for $3 \mathrm{h}$ deposits $2 \mathrm{g}$ of a metal during electrolysis. The quantity of the same metal that would be deposited by a current of $1.5 \mathrm{A}$ flowing in $1 \mathrm{h}$ is
Q8010.From the generating station to each substation, power is transmitted at a very high voltage so as to reduce
AHeating in the coils
BMagnetic flux leakage
CHysteresis loss
DEddy current loss.
Correct Answer: A
High voltage reduces current, minimizing heating in transmission cables.
JAMB (UTME)
Physics
2001
Q8011.Which of the following graphs shows the correct vector diagram for the circuit above?
A[Graph A]
B[Graph B]
C[Graph C]
D[Graph D]
Correct Answer: A
The correct vector diagram for an R-L circuit shows voltage across resistor in phase with current, and voltage across inductor leading by $90^{\circ}$.
JAMB (UTME)
Physics
2001
Q8012.The energy associated with the photon of a radio transmission at $3 \times 10^5 \mathrm{Hz}$ is
Q8013.The carbon-granule microphone works on the principle of change in
ACapacitance
BVoltage
CInductance
DResistance
Correct Answer: D
The carbon-granule microphone works on the principle of change in resistance.
Instruction
JAMB Physics 2002
JAMB (UTME)
Physics
2002
Q8014.Which of the following is the correct shape of the velocity-time graph of a spherical steel ball dropped into a viscous fluid in a tall cylinder?
A[Graph A - straight line increasing]
B[Graph B - horizontal line]
C[Graph C - straight line decreasing]
D[Graph D - curve increasing then flattening]
Correct Answer: D
The ball accelerates initially, then attains terminal velocity where the graph becomes horizontal.
JAMB (UTME)
Physics
2002
Q8015.A particle in circular motion performs 30 oscillations in 6 seconds. Its angular velocity is
A$6 \mathrm{rads}^{-1}$
B$5\pi \mathrm{rads}^{-1}$
C$10\pi \mathrm{rads}^{-1}$
D$5 \mathrm{rads}^{-1}$
Correct Answer: C
Frequency $f = \dfrac{30}{6} = 5 \mathrm{Hz}$. $\omega = 2\pi f = 2\pi \times 5 = 10\pi \mathrm{rads}^{-1}$.
JAMB (UTME)
Physics
2002
Q8016.A copper cube weighs $0.25 \mathrm{N}$ in air, $0.17 \mathrm{N}$ when completely immersed in paraffin oil and $0.15 \mathrm{N}$ when completely immersed in water. The ratio of upthrust in oil to upthrust in water is
A$13:10$
B$7:10$
C$3:5$
D$4:5$
Correct Answer: D
Upthrust in oil $= 0.25 - 0.17 = 0.08 \mathrm{N}$. Upthrust in water $= 0.25 - 0.15 = 0.10 \mathrm{N}$. Ratio $= \dfrac{0.08}{0.10} = \dfrac{4}{5}$.
JAMB (UTME)
Physics
2002
Q8017.The hydrostatic blood pressure difference between the head and feet of a boy standing straight is $1.65 \times 10^4 \mathrm{Nm}^{-2}$. Find the height of the boy. [Density of blood $= 1.1 \times 10^3 \mathrm{kgm}^{-3}$, $g = 10 \mathrm{ms}^{-2}$]
Q8018.If the total force acting on a particle is zero, the linear momentum will
ABe constant
BIncrease
CDecrease
DDecrease then increase
Correct Answer: A
If net force is zero, linear momentum is conserved (constant).
JAMB (UTME)
Physics
2002
Q8019.The effect of a particle in a fluid attaining its terminal velocity is that the
ABuoyancy force is more than the weight of the fluid displaced
BBuoyancy force is equal to the viscous retarding force
CAcceleration is maximum
DWeight is equal to the retarding force.
Correct Answer: D
At terminal velocity, weight = upthrust + viscous force, so net force is zero.
JAMB (UTME)
Physics
2002
Q8020.The diagram above shows the force-extension curve of a piece of wire. The energy stored when the wire is stretched from E to F is
A$7.5 \times 10^{-1} \mathrm{J}$
B$7.5 \times 10^{-1} \mathrm{J}$
C$2.5 \times 10^{-1} \mathrm{J}$
D$1.5 \times 10^{-1} \mathrm{J}$
Correct Answer: C
Energy $= \dfrac{1}{2}Fe = \dfrac{1}{2} \times 0.1 \times 0.05 = 0.0025 = 2.5 \times 10^{-3} \mathrm{J}$. The answer key C is incorrect.
JAMB (UTME)
Physics
2002
Q8021.If the distance between two suspended masses $10 \mathrm{kg}$ each is tripled, the gravitational force of attraction between them is reduced by
AOne ninth
BOne quarter
COne third
DOne half
Correct Answer: A
$F \propto \dfrac{1}{r^2}$. Tripling distance reduces force to $\dfrac{1}{9}$.
JAMB (UTME)
Physics
2002
Q8022.A wheel and axle is used to raise a load of $500 \mathrm{N}$ by the application of an effort of $250 \mathrm{N}$. If the radii of the wheel and the axle are $0.4 \mathrm{m}$ and $0.1 \mathrm{m}$ respectively, the efficiency of the machine is
Q8023.The diagram above shows the force (F) acting on an object through a distance (x). The work done on this object is expressed as
A$\dfrac{F}{x}$
B$Fx^2 \mathrm{J}$
C$\dfrac{Fx}{2}$
D$Fx \mathrm{J}$
Correct Answer: C
Work done = area under graph = $\dfrac{1}{2}Fx$.
JAMB (UTME)
Physics
2002
Q8024.A body weighing $80 \mathrm{N}$ stands in an elevator that is about to move. The force exerted by the floor on the body as the elevator moves upwards with an acceleration of $5 \mathrm{ms}^{-2}$ is $[g = 10 \mathrm{ms}^{-2}]$
Q8025.Two forces each of $10 \mathrm{N}$ act on a body, one towards north and the other towards the east. The magnitude and the direction of the resultant force are
A$20 \mathrm{N}, 45^{\circ}\mathrm{W}$
B$10\sqrt{2} \mathrm{N}, 45^{\circ}\mathrm{W}$
C$10\sqrt{2} \mathrm{N}, 45^{\circ}\mathrm{E}$
D$20 \mathrm{N}, 45^{\circ}\mathrm{E}$
Correct Answer: C
$R = \sqrt{10^2 + 10^2} = 10\sqrt{2} \mathrm{N}$. Direction is $45^{\circ}$ East of North.
JAMB (UTME)
Physics
2002
Q8026.A ray of light which strikes a glass slab from air at normal incidence passes through the slab
AUndeviated and displaced at a faster speed
BUndeviated and undisplaced at a lower speed
CDeviated and undisplaced at a lower speed
DDeviated and displaced at a lower speed.
Correct Answer: B
At normal incidence, light passes undeviated and undisplaced, but at a lower speed in glass.
JAMB (UTME)
Physics
2002
Q8027.Which of the following is a characteristic of stationary waves?
AThe distance between two successive nodes is one wavelength.
BThey are formed by two identical waves traveling in opposite directions.
CThe antinode is a point of minimum displacement.
DThey can be transverse or longitudinal.
Correct Answer: B
Stationary waves are formed by two identical waves traveling in opposite directions.
JAMB (UTME)
Physics
2002
Q8028.Which of the following eye defects can be corrected using a cylindrical lens?
APresbyopia
BChromatic aberration
CMyopia
DAstigmatism
Correct Answer: D
Astigmatism is corrected using a cylindrical lens.
JAMB (UTME)
Physics
2002
Q8029.The property that is propagated in a traveling wave is
AAmplitude
BWavelength
CFrequency
DEnergy
Correct Answer: D
Energy is propagated in a traveling wave.
JAMB (UTME)
Physics
2002
Q8030.A concave mirror of radius of curvature $40 \mathrm{cm}$ forms a real image twice as large as the object. The object distance is
Q8031.If tension is maintained on a stretched string of length $0.6 \mathrm{m}$ such that its fundamental frequency of $220 \mathrm{Hz}$ is excited, determine the velocity of the transverse wave in the string.
Q8033.A coin placed below a rectangular glass block of thickness $9 \mathrm{cm}$ and refractive index $1.5$ is viewed vertically above the block. The apparent displacement of the coin is
Q8034.Blowing air over a liquid aids evaporation by
ADecreasing its vapour pressure
BDecreasing its density
CIncreasing its surface area
DIncreasing its temperature
Correct Answer: A
Blowing air removes vapour molecules, decreasing vapour pressure and aiding evaporation.
JAMB (UTME)
Physics
2002
Q8035.The pressure of 3 moles of an ideal gas at a temperature of $27^{\circ}\mathrm{C}$ having a volume of $10^{-3} \mathrm{m}^3$ is $[R = 8.3 \mathrm{Jmol}^{-1}\mathrm{K}^{-1}]$
A$7.47 \times 10^5 \mathrm{Nm}^{-2}$
B$2.49 \times 10^6 \mathrm{Nm}^{-2}$
C$7.47 \times 10^6 \mathrm{Nm}^{-2}$
D$2.49 \times 10^5 \mathrm{Nm}^{-2}$
Correct Answer: A
$P = \dfrac{nRT}{V} = \dfrac{3 \times 8.3 \times 300}{10^{-3}} = 7.47 \times 10^6 \mathrm{Nm}^{-2}$. The answer key A is incorrect; the correct answer is C.
JAMB (UTME)
Physics
2002
Q8036.To produce an enlarged and erect image with a concave mirror, the object must be positioned
ABetween the principal focus and the pole
BBetween the principal focus and the centre of curvature
CBeyond the centre of curvature
DAt the principal focus
Correct Answer: A
A concave mirror produces a virtual, erect, and magnified image when the object is between the pole and the focus.
JAMB (UTME)
Physics
2002
Q8037.The colours seen in soap bubbles are due to
ARefraction
BDiffraction
CInterference
DDispersion
Correct Answer: C
The colours are due to interference of light reflected from the top and bottom surfaces of the soap film.
JAMB (UTME)
Physics
2002
Q8038.The phenomenon that makes sound persist when its source has been removed is known as
AReverberation
BAcoustic vibration
CRarefaction
DEcho
Correct Answer: A
Reverberation is the persistence of sound after the source has stopped.
JAMB (UTME)
Physics
2002
Q8039.Vibrations in a stretched spring cannot be polarized because they are
ALongitudinal waves
BMechanical waves
CStationary waves
DTransverse waves.
Correct Answer: A
Longitudinal waves cannot be polarized.
JAMB (UTME)
Physics
2002
Q8040.I. Temperature
AI, II and IV only
BI and II only
CI, II, III and IV
DII and IV only.
Correct Answer: B
Velocity of sound in air depends on temperature and density of air molecules.
JAMB (UTME)
Physics
2002
Q8041.Water is a poor thermometric liquid because
AWets glass
BHas low vapour pressure
CIs opaque
DIs a poor conductor
Correct Answer: A
Water wets glass, making it difficult to read the meniscus.
JAMB (UTME)
Physics
2002
Q8042.The time rate of loss of heat by a body is proportional to the
ATemperature of its surroundings
BDifference in temperature between the body and its surrounding
CTemperature of the body
DRatio of the temperature of the body to that of its surrounding.
Correct Answer: B
According to Newton's law of cooling, rate of heat loss is proportional to the temperature difference.
JAMB (UTME)
Physics
2002
Q8043.An electric iron is rated $1000 \mathrm{W}$, $230 \mathrm{V}$. What is the resistance of its element?
Q8044.The electric field between the two-point charges is shown in the diagram above. What types of charges are at X and Y?
ABoth X and Y are positive
BX is positive and Y is negative
CX is negative and Y is positive
DBoth X and Y are negative.
Correct Answer: D
The field lines converge towards both X and Y, indicating both are negative.
JAMB (UTME)
Physics
2002
Q8045.The eye controls the amount of light reaching the retina by adjusting the
AIris
BOptic nerve
CCornea
DRetina
Correct Answer: A
The iris controls the pupil size, regulating light entering the eye.
JAMB (UTME)
Physics
2002
Q8046.An electric cell with nominal voltage E has a resistance of $3 \Omega$ connected across it. If the voltage falls to $0.6 \mathrm{V}$, the internal resistance of the cell is
A$2 \Omega$
B$4 \Omega$
C$1 \Omega$
D$3 \Omega$
Correct Answer: A
$V = E - Ir$. $0.6 = E - \dfrac{E}{3 + r} \times r$. This requires more information.
JAMB (UTME)
Physics
2002
Q8047.When connected to a mains $250 \mathrm{V}$, the fuse rating in the plug of an electric device of $1 \mathrm{kW}$ is
A$5 \mathrm{A}$
B$4 \mathrm{A}$
C$3 \mathrm{A}$
D$2 \mathrm{A}$
Correct Answer: A
$I = \dfrac{P}{V} = \dfrac{1000}{250} = 4 \mathrm{A}$. A $5 \mathrm{A}$ fuse is suitable.
JAMB (UTME)
Physics
2002
Q8048.The electromagnetic wave that can produce a heating effect on the environment is
AGamma rays
BX-rays
CUltraviolet rays
DInfrared rays.
Correct Answer: D
Infrared rays produce heating effects.
JAMB (UTME)
Physics
2002
Q8049.The energy stored in a capacitor of capacitance $10 \mu\mathrm{F}$ carrying a charge of $100 \mu\mathrm{C}$ is