JAMB UTME - Physics - 1983 | Green Bridge CBT

Question 1 Report

Which of the following may be used to determine relative humidity in a physics laboratory?
I. Manometer
II. Wet-and-dry bulb hygrometer
III. Hair hygrometer
IV. A hydrometer.

III only

I only

II only

II and III only

Temperature And Its Measurement

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Question 2 Report

An electric current of 3Aflowing through an electric heating elements of resistance 20 embedded in 1,000g of an oil raises the temperature of the oil by 10oC in 10 seconds then the specific heat capacity of the oil is

1.8Jg-1oC

0.6Jg-1oC

0.18Jg-1oC

18Jg-1oC

0.06Jg-1oC

Answer Details

Heat energy = Electrical energy

mc $Ω$ = I2RTt

1000 x c x 10 = 3 x 3 x 20 x 10

0.18Jg-1oC

Read lesson note on Heat Energy (WAEC)

Heat Energy

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Question 3 Report

a force of 16N applied 4.0kg block that is at rest on a smooth, horizontal surface. What is the velocity of the block at t = 5 seconds?

4ms-1

10ms-1

20ms-1

50ms-1

80ms-1

Answer Details

F = ma

= $\frac{m (u - v)}{t}$

16 = $\frac{4 (v - 0)}{5}$

v = 20ms-1

Read lesson note on Newton’s Laws Of Motion (WAEC)

Newton’s Laws Of Motion

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Question 4 Report

A machine has a velocity ratio of 5. It requires a 50kg weight to overcome a 200kg weight. The efficiency is

4%

5%

40%

50%

80%

Answer Details

Efficiency = M.A x 100%

= $\frac{200}{50}$ x $\frac{1}{5}$ x 100

= 80%

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Question 5 Report

Which of the following is NOT a vector quantity?

Force

Altitude

weight

Displacement

Acceleration

Scalars And Vectors

Measurements And Units

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Question 6 Report

A milliameter with full scale deflection of 10mA has an internal resistance of 5 ohms. It would be converted to an ammeter with a full scale deflection of 1A by connecting a resistance of

\frac{5}{99}

ohms in series with it

\frac{5}{99}

ohms in parallel with it

\frac{99}{5}

ohms in series with it

\frac{99}{5}

ohms in parallel with it

2 ohms in series with it

Answer Details

I = 1 - (10 x 10-3)

= 0.99A

IR = 10 x 10 x 10-3 x 5

R = $\frac{5}{99}$ $Ω$

Read lesson note on Capacitors (JAMB)

Capacitors

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Question 7 Report

The specific latent heat of vaporization of a substance is always

less than its specific latent heat of fusion

greater than its specific heat of fusion

equal to its specific latent heat of fusion

all of the above depending on the nature of the substance

none of the above

Quantity Of Heat

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Question 8 Report

Which of the following arrangements in the sequence shown can be used to obtain a pure spectrum of white light?

source, slit, converging lens, prism, converging lens, screen.

source, slit, diverging lens, prism, diverging lens, screen.

source, converging lens, prism, diverging lens, screen.

source, slit, prism, diverging lens, converging lens, screen

source, slit, prism, diverging lens, sreen.

Electromagnetic Waves: Types Of Radiation In Elect

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Question 9 Report

If the pressure on 100cm3 of an ideal gas is doubled while its kelvin temperature is halved, then the new volume of the gas will become

25cm3

50cm3

100cm3

200cm3

400cm3

Answer Details

$\frac{P_{1} V_{1}}{T_{1}}$ = $\frac{P_{2} V_{2}}{T_{2}}$

P2 = 2P ; T1 = 2T2

therefore, $\frac{P_{1} \times 1000}{2 T_{2}}$ = $\frac{2 P_{2} \times V_{2}}{T_{2}}$

= 25cm

Read lesson note on Pressure (JAMB)

Pressure

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Question 10 Report

Which of the following conditions are necessary and sufficient for total internal reflection to take place at the boundary between two optical media? i. light is passing from optically denser medium to optically less dense medium. ii. light is passing from optically less dense medium to optically denser medium. iii. angle of incidence is greater. iv. angle of incidence is lesser

i and ii only

ii and iii only

ii and iv only

i and iii only

Reflection Of Light At Plane And Curved Surfaces

Refraction Of Light Through At Plane And Curved

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Question 11 Report

In a resonance tube experiment, a tube of fixedlength in closed at one end and several turningforks of increasing frequency used to obtainresonance at the open end. If the turning fork withthe lowest frequency which gave resonance had a frequency f1 and the next turning fork to giveresonance had a frequency f2, find the ratio f2/ f1.

2

3

1/2

8

Position, Distance And Displacement

Thermal Expansion

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Question 12 Report

The speed of light in vacuum is 3.0 x 108ms-1. If the refractive index of a transparent liquid is $\frac{4}{3}$ , then the speed of light in the liquid is

0.44 x 10 8ms-1

2.25 x 10 8ms-1

3.0 x 10 8ms-1

4.0 x 10 8ms-1

4.33 x 10 8ms-1

Answer Details

n = $\frac{speed in air}{speed in water}$

$\frac{4}{3}$ = $\frac{3 \times 10^{8}}{v}$

v = 2.25 x 10 8ms-1

Read lesson note on Motion (JAMB)

Motion

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Question 13 Report

A ship travelling towards a cliff receives the echo of its whistle after 3.5 seconds. A short while later, it receives the echo after 2.5 seconds. If the speed of sound in air under the prevalling condition is 250ms -1, how much closer is the ship to the cliff?

10m

125m

175m

350m

1,000m

Answer Details

Difference in time = 1 sec.

echo time = 1 $\div$ 2 = 0.5 sec.

= 0.5 x 250

= 125m

Read lesson note on Properties Of Waves: Reflection, Refraction, Diffraction (WAEC)

Properties Of Waves: Reflection, Refraction, Diffraction

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Question 14 Report

Ripples on water are similar to light waves in that they both

have the same wavelength

are longitudinal

cannot be reflected

travel at the same speed

can be refracted and diffracted

Light Waves

Properties Of Waves: Reflection, Refraction, Diffraction

Change Of State

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Question 15 Report

In a resonance tube experiment, a tube fixed length is closed at one end and several tuning forks of increasing frequency used to obtain resonance at the open end. If the tuning fork with the lowest frequency which gave resonance had a frequency f1 and the next tuning fork to give resonance had a frequency f2, find the ratio $\frac{f^{2}}{f^{2}}$ .

8

3

2

1

2

1

3

Answer Details

λ_{1}

= 4L1 and

λ_{2}

= -L1

F $λ$ = velocity

F1 x $λ_{1}$ = F2 x
$λ_{2}$ ; F1 x 4 $λ_{1}$ = F2 x - $λ_{2}$

= $\frac{F_{2}}{F_{1}}$ = 3

Read lesson note on Newton’s Laws Of Motion (WAEC)

Read lesson note on Motion (JAMB)

Read lesson note on Work, Energy And Power (WAEC)

Newton’s Laws Of Motion

Motion

Work, Energy And Power

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Question 16 Report

Which of the following best describes the energy changes which take place when a steam engine drives a generator which lights a lamp?

heat

\to

light

\to

sound

\to

kinetic

\to

light

\to

heat

\to

electricity

heat

\to

kinetic

\to

electricity

\to

heat

\to

light

electricity

\to

kinetic

\to

heat v light

heat

\to

sound

\to

kninetic v electricity

Current Electricity

Heat Energy

Work, Energy And Power

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Question 17 Report

The total length of a spring when a mass of 20g is hung from its end is 14cm, while its total length is 16cm when a mass of 30g is hung from the same end. Calculate the unstretched length of the spring assuming Hooke's law is obeyed.

9.33cm

10.00cm

10.66cm

12.00cm

15.00cm

Answer Details

Let unstretched length = L

e1 = 14 - L and e2 = 16 - L

Using, $\frac{m_{1}}{e_{1}}$ = $\frac{m_{2}}{e_{2}}$

$\frac{20}{14 - L}$ = $\frac{30}{16 - L}$

L = 10cm

Read lesson note on Elasticity (JAMB)

Elasticity

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Question 18 Report

1,000 identical drops of oil of density 500kgm-3 have a total mass of 5 x 10-4kg. One of the drops forms a thin film of area 0.5m2 on water. The thickness of the film is

2 x 10-8m

2 x 10-9m

2 x 10-7m

3 x 10-9m

2.8 x 10-8m

Answer Details

Mass of one oil = $\frac{5 \times 10^{- 4}}{1000}$

= 5 x 10-4kg

Density = $\frac{mass}{area x thickness}$

500 = $\frac{5 \times 10^{- 7}}{0.5 x thickness}$

thickness = 2 x 10-9m

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Question 19 Report

A short response to time is obtained in liquid-in-glass thermometer when the

bulb is large and thick-walled

stem is long and thin

bulb is small and thicked-walled

liquid is of high density and the bore is large

bulb is thin-walled and the liquid is a good conductor of heat

Temperature And Its Measurement

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Question 20 Report

which of the following is NOT correct? i. the pitch of a sound note depends on the frequency of vibrations. ii. the intensity of a sound note is proportional to the amplitude of vibrations. iii. beats are produced by two sources of sound because one wave is travelling faster than the other. iv. when two sources of sound of frequencies 500Hz and 502Hz are sounded together, a beat frequency of 2Hz is observed. v. the first harmonic of a tone have double the frequency of the fundamental note.

i and ii

ii and iii

i and iii

iii and iv

iv and v

Current Electricity

Sound Waves

Reflection Of Light At Plane And Curved Surfaces

Magnets And Magnetic Fields

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Question 21 Report

Each of the figures in the diagram above represent two current carrying conductors situated close to each other. In which two diagrams, are the forces between the two wires attractive

I and V

I and II

II and IV

II and V

III and IV

Newton’s Laws Of Motion

Force On A Current-carrying Conductor In A Magneti

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Question 22 Report

The linear expansivity of brass is 2 x 10-5oC-1. If the volume of a piece of brass is 10cm3 at 0oC, what will be its volume at 100oC?

10.02cm3

10.04cm3

10.06cm3

10.20cm3

102.00cm3

Answer Details

3 x $α$ = $\frac{V_{2} - V_{1}}{Δ θ \times V_{1}}$

3 x 2 x 10-5 = $\frac{V_{2} - 10}{10 \times 100}$

V2 = 10.06cm3

Read lesson note on Temperature And Its Measurement (JAMB)

Temperature And Its Measurement

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Question 23 Report

A train has an initial velocity of 44ms-1 and an acceleration of -4ms-1. Its velocity after 10 seconds is

2ms-1

4ms-1

8ms-1

12ms-1

16ms-1

Motion

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Question 24 Report

The refractive index of liquid is 1.5. If the velocity of light in vacuum is 3.0 x 108ms-1, the velocity of light in the liquid is

1.5 x 108m-1

2.0 x 108m-1

3.0 x 108m-1

4.5 x 108m-1

9.0 x 108m-1

Answer Details

n = $\frac{speed in air}{speed in glass}$

1.5 = $\frac{3 \times 10^{4}}{speed in glass}$

speed in glass = 2 x 108ms-1

Read lesson note on Electromagnetic Waves: Types Of Radiation In Elect (WAEC)

Electromagnetic Waves: Types Of Radiation In Elect

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Question 25 Report

The difference of potential between the terminals of cells is 2.2 volts. When a 4ohm resistor is connected across the terminals of this cells, the potential difference is 2 volts. What is the internal resistance of the cell?

0.10 ohms

0.25ohms

0.40ohms

2.50ohms

4.00ohms

Answer Details

IR = 2 and Ir = 0.2

I = $\frac{2}{R}$ ; I = $\frac{0.2}{r}$

$\frac{2}{4}$ = $\frac{0.2}{r}$

r = 0.4 $Ω$

Read lesson note on Current Electricity (JAMB)

Read lesson note on Electrical Energy And Power (JAMB)

Read lesson note on Electric Cells (JAMB)

Current Electricity

Electrical Energy And Power

Electric Cells

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Question 26 Report

Which of the following figures gives the correct resultant R of two vectors P and Q?

I

II

III

IV

V

Scalars And Vectors

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Question 27 Report

PQ is a thin rod on a horizontal table, RS is a plane mirror inclined at $45^{\circ} C$ to the horizontal as shown above. The image of PQ as seen in the mirror by the eye T is

horizontal

parallel to the mirror

at infinity

vertical

highly magnified

Electrostatics

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Question 28 Report

A man of mass 50kg ascends a flight of stairs 5m high in 5 seconds. If acceleration due to gravity is 10ms-2, the power expended is

100W

200W

250W

400W

500W

Answer Details

Power = $\frac{force x distance}{time}$

= 50 x 10 x 5 = 500W

Read lesson note on Gravitational Field (JAMB)

Gravitational Field

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Question 29 Report

Which of the following statements is true about liquid pressure is NOT correct? The pressure

at a point in a liquid is proportional to the depth

at any point in a liquid is the same at the same level

is exerted equally in all directions at any point

of a liquid at any point on the wall of its container acts in a direction perpendicular to the wall

at a particular depth depends on the shape of the vessel

Pressure

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Question 30 Report

The image above shows an inverted U-tube with the open end, O of one limb below the level, W of water in the tank, in order that water should begin to flow from the tank it is is necessary that

The U-tube is completely filled with water and that P should be higher that W

P should be lower than O and W

P should be lower than W and O should reach the botton of the table

The U-tube is completely filled with water and that P should be lower that W

Fluid At Rest

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Question 31 Report

A piece of wood is floating on water. The forces acting on the wood are

upthrust and reaction

weight and reaction

weight and upthrust

upthrust and viscousity

weight and viscousity

Gravitational Field

Measurements And Units

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Question 32 Report

Which of the following statements about defects of vision is/are CORRECT? i. for a long sighted person, close objects appear blurred. ii. for a short sighted person, distant objects appear blurred. iii. short sight is corrected by using a pair of converging lenses.

i only

ii only

i and ii only

ii and iii only

i, ii and iii

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Question 33 Report

If the force of a charge of 0.2 coulomb in an electric field is 4N, then the electric field intensity of the field is

0.8

0.8N/C

20.0N/C

4.2N/C

Answer Details

Field intensity = $\frac{f o r c e}{c h a r g e}$

$\frac{4}{0.2}$ = 20N/C

Read lesson note on Electric Field (WAEC)

Electric Field

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Question 34 Report

Four resistors R1, R2, R3 and R4 are connected in series as shown above, V1, V2, V3 are voltmeters connected as indicated above. Which of the following relations is correct??

V1 = V3 =V2/2

V1 = 2V2 = V3

V1=1/2V3 =V3

V2 - V1 = V3

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Question 35 Report

In the Figure above, QR is a vertical conductor and the current I flows from R to Q, P is a point on the horizontal plane and is to the south of the wire. The direction of the magnetic field at P due to the current is

Upward

North

South

West

East

Force On A Current-carrying Conductor In A Magneti

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Question 36 Report

The diagram above shows three circuits, the internal resistances of the batteries are negligible. which of the currents is the largest

I1

I2

I3

I4

I5

Capacitors

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Question 37 Report

Which of the following may be used to determine the relative humidity in a physics laboratory I. Manometer

II. Wet-and-Dry Bulb Hygrometer

III. Hair Hygrometer

IV. A Hydrometer

I Only

II and III Only

II Only

III Only

II,IIIand IV Only

Liquids At Rest

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Question 38 Report

The force with which an object is attracted to the earth is called its

acceleration

mass

gravity

impulse

weight

Gravitational Field

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Question 39 Report

If the normal atmospheric pressure in a laboratory supports a column of mercury 0.76m high and the relative density of mercury is 13.8, then the height of water column which atmospheric pressure will support in the same laboratory at the same time is

0m

10m

13m

14m

18m

Pressure

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Question 40 Report

Longitudinal waves do not exhibit

Refraction

Reflection

Diffraction

Polarization

Rarefaction

Sound Waves

Properties Of Waves: Reflection, Refraction, Diffraction

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Question 41 Report

Which of the following statements is CORRECT? i. the mass number is equal to the total number of protons and electrons in an atom. ii. the atomic number is equal to the number of protons in an atom. iii. the number of electrons in an atom is equal to the total number of protons and neutrons in the nucleus.

i only

ii only

iii only

i and ii only

ii and iii only

Structure Of The Atom (Nigeria Only)

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Question 42 Report

Which of the following statements about friction is NOT correct?

The force of kinetic friction is less than the force of static friction

The force of kinetic friction between two surfaces is independent of the areas in contact provided the normal reaction is unchanged

The force of rolling friction between two surfaces is less than the force of sliding friction

The angle of friction is the angle between the normal reaction and the force of friction

Friction may be reduced by lubriction

Friction

Measurements And Units

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Question 43 Report

The electrochemical equivalent of a metal is 0.126 x 10-6 kgC-1. The mass of the metal that a current of 5A will deposit from a suitable bath in 1 hour is

0.0378 x 10 -3kg

0.227 x 10 -3kg

0.378 x 10 -3kg

0.595 x 10 -3kg

2.268 x 10 -3kg