JAMB UTME - Physics - 1984 | Green Bridge CBT

Question 1 Report

Cathode rays are

high-energy electromagnetic waves

protons

streams of electrons

neutrons

radio waves

Electrostatics

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Question 2 Report

Which of the following can be described as high tension transmission?

high resistance and low voltage

low current and high voltage

high current and low voltage

high voltage and zero current

high current and low resistance

Electric Field

Magnetic Field (Part 1)

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Question 3 Report

What is the cost of running five 50W lamps and four 100W lamps for 10 hours if electrical energy costs 2 kobo per kWh?

N0.65

N0.13

N3.90

N39.00

N234.00

Answer Details

PT = (5 x 50) + (100 x 4)

= 650watts

Energy(kWhr) = 650 x 10-3 x 10

= 6.5 kWhr

1kWhr cost 2 kobo ; 6.5 kWhr will cost $\frac{2 \times 6.5}{1}$

= 13 kobo

Read lesson note on Heat Transfer (JAMB)

Read lesson note on Electrical Energy And Power (JAMB)

Heat Transfer

Electrical Energy And Power

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Question 4 Report

A force varying linearly with the distance acts on a body as shown above, The work done on the body by the force during the first 10m of motion is

100J

150J

200J

300J

600J

Equilibrium Of Forces

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Question 5 Report

A device that converts sound energy into electrical energy is

the horn of a motor car

an A.C. generator

a microphone

the telephone

radio waves

Electrostatics

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Question 6 Report

Which of the following properties of matter CANNOT be utilized for temperature measurement? The

length of a liquid column

volume of a gas at constant pressure

pressure of a gas at constant volume

resistance of a metallic wire

current produced in a photoelectric effect

Current Electricity

Wave-particle Paradox

Scalars And Vectors

Temperature And Its Measurement

Conduction Of Electricity Through

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Question 7 Report

When vibration occurs in air column, the distance between a node and an antinode is equal to

one-quarter of the wavelength

one-hall of the wavelength

the wave length

twice the wavelength

four-times the wavelength

Current Electricity

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Question 8 Report

What is the resistance of the circuit shown above

4Ω

11Ω

19/5Ω

17/4Ω

8Ω

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Question 9 Report

Of two identical tuning forks with natural frequency 256Hz, one is loaded so that 4 beats per second are heard when they are sounded together. What is the frequency of the loaded tuning fork?

260Hz

252Hz

248Hz

264Hz

258Hz

Answer Details

Beat = F2 - F1

4 = F2 - 256

F2 = 260Hz

Read lesson note on Current Electricity (JAMB)

Read lesson note on Propagation Of Sound Waves (JAMB)

Current Electricity

Propagation Of Sound Waves

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Question 10 Report

Which of the following statements about the compound microscope and astronomical telescope is (are) correct? i. the final image of a compound microscope is located at infinity ii. the final image of the astronomical telescope is always erect iii. the objective lens of a compound microscope has a very short focal length

i only

ii only

iii only

i and iii

ii and iii

View Answer

Question 11 Report

A simple pendulum, 0.6m long, has a period of 1.5s. What is the period of a similar pendulum of 0.4m length in the same location?

1.5 \frac{\sqrt{2}}{3}

s

1.5 \frac{\sqrt{3}}{2}

s

2.25s

1.00s

2.00s

Equilibrium Of Forces

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Question 12 Report

What is the apparent colour of a RED SHIRT when viewed in PURE green light?

Red

Green

Yellow

Black

Blue

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Question 13 Report

In the circuit Shown above, calculate the effective capacitance between X and Y

3/4µF

2 \frac{10}{13} µ F

12µF

4	12	µF
	13

13µF

Capacitors

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Question 14 Report

Which of the following statements is (are) NOT correct? i. pressure changes do not affect the speed of sound in air ii. the velocity of sound increases with temperature iii. the quality of the note depends only on its frequency

i only

ii only

iii only

i and iii

ii and iii

Properties Of Waves: Reflection, Refraction, Diffraction

Pressure

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Question 15 Report

Which of the following is a correct explanation of the inertia of a body?

ability to overcome the earth's gravity

reluctance to stop moving

readiness to start moving

reluctance to start moving and its readiness to stop moving once it has begun to move

reluctance to start moving its reluctance to stop moving once it has begun to move

Newton’s Laws Of Motion

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Question 16 Report

Which of the following statements describes an atom accurately? i. atoms of all elements are identical ii. an atom contains a nucleus and number of electrons iii. due to the electrons in the atom an atom is negatively charged iv. electrons in the atom move in circular orbits round the nucleus

i and ii

ii and iii

iii and iv

ii and iv only

i,ii and iii

Structure Of The Atom (Nigeria Only)

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Question 17 Report

Which of the following i. $ \beta $-particles ii. protons iii. neutrons iv. $ \alpha $-particles. may be found in light nuclei?

i and ii

i and iii

ii and iv

ii and iii

i, ii and iii

Structure Of The Atom (Nigeria Only)

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Question 18 Report

For which of the underlisted quantities is the derived unit ML2T2 correct? i. momentum of a force ii. work iii. acceleration

i only

ii only

iii only

i and ii

ii and iii

Answer Details

Moment = force x distance

= m x a x d

= kg x $\frac{m}{s^{2}}$ x $\frac{m}{1}$

= ML2T2

Read lesson note on Fundamental And Derived Quantities And Units (WAEC)

Fundamental And Derived Quantities And Units

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Question 19 Report

If a water pump at Kainji Dam is capable of lifting 1000kg of water through a vertical height of 10m in 10s, the power of the pump is [g = 10ms-2]

1.0kW

10.0kW

12.5kW

15.0kW

20.0kW

Answer Details

power =

\frac{work done}{t i m e}

= $\frac{1000 \times 10 \times 10}{10}$

= 10kW

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

Work, Energy And Power

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Question 20 Report

The resistance of a wire depends on

the length of the wire

the diameter of the wire

the temperature of the wire

the resistivity of the wire

all of the above

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Question 21 Report

The lower and upper fixed points marked on a mecury-in-glass thermometer are 210mm apart. The end of the mercury column in the tube is 49mm above the lower fixed point in a room. What is the temperature of the room in degrees Celsius?

55.3oC

23.3oC

49.0oC

16.1oC

76.7oC

Answer Details

210mm .... 100oC

49mm .... $θ$

0mm .... 0oC

$\frac{49 - 0}{210 - 0}$ = $\frac{θ - 0}{100 - 0}$

$\frac{49}{210}$ = $\frac{θ}{100}$

$θ$ = 23.3oC

Read lesson note on Temperature And Its Measurement (JAMB)

Temperature And Its Measurement

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Question 22 Report

Two cells each of e.m.f. 1.5V and an internal resistance $2\ \Omega$ are connected in parallel. Calculate the current flowing when the cells are connected to a $1\ \Omega$ resistor

0.75

Ω

Ω

1.5

Ω

0.5

Ω

1.0

Ω

0.6

Ω

Answer Details

E = 1.5v

rT = $\frac{2 \times 2}{2 + 2}$
= 1

e.m.f. = I(R + r)

1.5 = I(1 + 1)

I = 0.75 $Ω$

Read lesson note on Current Electricity (JAMB)

Read lesson note on Electric Cells (JAMB)

Current Electricity

Electric Cells

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Question 23 Report

A gun of mass 2.0kg fires a bullet of mass 16 x 10 -2kg due East. If the bullet leaves the nozzle of the gun with a velocity of 150ms-1, what is the recoil velocity of the gun?

150ms-1 due West

1.2 x 10-4ms-1 due West

1.2ms-1 due West

1.2ms-1 due East

150ms-1 due East

Answer Details

Gun momentum = bullet momentum

2 x v = 1.6 x 10-2 x 150

v = 1.2ms-1 in opposite direction

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

Newton’s Laws Of Motion

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Question 24 Report

A body of mass 5kg initially at rest is acted upon by two mutually perpendicular forces 12N and 5N as shown in fig.3. If the particle moves in the direction QA, calculate the magnitude of the acceleration

0.40ms-2

1.40ms-2

0.26ms-2

2.60ms-2

3.40ms-2

Answer Details

R =

\sqrt{12^{2} + 5^{2}}

R = 13N and R = F = ma

13 = 5 x a

= 2.60ms-2

Read lesson note on Scalars And Vectors (WAEC)

Read lesson note on Equilibrium Of Forces (WAEC)

Scalars And Vectors

Equilibrium Of Forces

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Question 25 Report

The distance travelled by a particle starting from rest is plotted against the square of the time elapsed from the commencement of motion. The resulting graph is linear, the slope of this graph is a measure of

initial displacement

initial velocity

acceleration

half the acceleration

half the initial velocity

Position, Distance And Displacement

Equilibrium Of Forces

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Question 26 Report

Which of the following components is NOT contained in a dry cell? A

carbon rod

paste of magnesium dioxide

paste of ammonium chloride

zinc case

copper rod

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Question 27 Report

All the heat generated in a $5\ \Omega$ resistor by 2A flowing for 30 seconds is used to evaporate 5g of a liquid at its boiling point. Which of the following is the correct value of the specific latent heat of the liquid?

120J

60Jg-1

120Jg-1

1500J

1500Jg-1

Answer Details

Heat energy = electrical energy

mL = I2Rt

5 x L = 2 x 2 x 5 x 30

L = 120Jg-1

Read lesson note on Heat Energy (WAEC)

Heat Energy

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Question 28 Report

A given mass of an ideal gas occupies a volume V at a temperature T and under a pressure p. If the pressure is increased to 2p and the temperature reduced to $ \frac{1}{2T} $, then the percentage change in the volume of the gas is

0%

25%

75%

300%

400%

Answer Details

\frac{P_{2} V_{2}}{T_{2}}

=

\frac{P_{1} V_{1}}{T_{1}}

P2 = 2P1

T1 = 2T2

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

V2 --V1

% change = $\frac{V_{1} - \frac{1}{4} V_{1}}{V_{1}}$ X 100%

= 75%

Read lesson note on Light Waves (WAEC)

Light Waves

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Question 29 Report

If a solid changes directly into a gas when heat is applied the process is called

vaporization

evaporation

sublimation

ionization

conversion

Vapours

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Question 30 Report

Dewpoint is the temperature at which, water vapour in the atmosphere

turns into steam

solidifies into ice pellets

first condenses into liquid form

is just sufficient to cause cooling

has a relative humidity of fifty percent

Vapours

Temperature And Its Measurement

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Question 31 Report

A plane inclined at an angle of 30o to the horizontal has an efficiency of 60%. The force parallel to the plane required to push a load of 120N uniformly up the plane is

60N

100N

120N

200N

240N

Answer Details

V.R =

\frac{1}{s i n 30}

= 2

Efficiency = $\frac{m . A}{V . R}$ x 100%

60 = $\frac{120}{e f f o r t}$ x $\frac{1}{2}$ x 100

Effort = 100N

Read lesson note on Equilibrium Of Forces (WAEC)

Equilibrium Of Forces

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Question 32 Report

A particle moves in a circular orbit of radius 0.02m. If the speed of the particle is 0.88ms-1, calculate its frequency in cycles per second

2.0Hz

7.0Hz

8.8Hz

14.0Hz

17.6Hz

Answer Details

W =

\frac{v}{r}

= $\frac{0.88}{0.02}$ = 44 rad/s

2 $π$ F = W = 44

F = $\frac{44}{2 \times 3.142}$

= 7Hz

View Answer

Question 33 Report

A galvanometer of resistance 5.0W has full-scale deflection for a current of 100mA. How would its range be extended to 1.0A? By placing a resistance of

\frac{5}{9}

Ω

in parallel

\frac{9}{5}

Ω

in series

45

Ω

in parallel

45

Ω

in series

\frac{9}{5}

Ω

in parallel

Structure Of The Nucleus

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Question 34 Report

For a concave mirror to form a teal diminished image, the object must be placed

behind the mirror

between the mirror and its focus

between the focus and the centre of curvature

at the centre of curvature

at a distance greater than the radius of curvature

Reflection Of Light At Plane And Curved Surfaces

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Question 35 Report

A small steel needle is carefully floated on water in a beaker. When a few drops of kerosine are introduced into the water the needle sink. Which of the following statements correctly explain(s) the observation? i. there is tension on the water surface ii. kerosine reduces the density of water so that needle becomes denser than water iii. kerosine reduces the surface tension of water

i only

ii only

iii only

i and ii

i and iii

View Answer

Question 36 Report

A short bar magnet is placed in earth's magnetic field, as shown above, which of the points II and III are/is possible positions of a neutral point?

I only

II only

III only

I and II

I,II and III

Magnets And Magnetic Fields

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Question 37 Report

Radio waves have a velocity of 3 x 108ms-1. A radio station sends out a broadcast on a frequency of 800kHz. The wavelength of the broadcast is

375.0m

267.0m

240.0m

37.5m

26.7m

Answer Details

v = F

λ

3 x 108 = $λ$ x 800 x 103

$λ$ = 375.0m

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

Electromagnetic Waves: Types Of Radiation In Electromagnetic Spectrum

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Question 38 Report

A coin is placed at the bottom of a cube of glass tern thick. If the refractive index of the glass is $ \mu $, how high does the coin appear to be raised to an observer looking perpendicularly into the glass?

1

t−μ

\frac{t (μ - I)}{μ}

t (1 +

\frac{1}{μ}

)

-

μ

μ

t

Answer Details

Let apparent depth = X

$μ$ = $\frac{t}{x}$ $\Rightarrow$ X = $\frac{t}{u}$

raised of coin = t - x

= t - $\frac{t}{μ}$

= $\frac{t (μ - I)}{μ}$

Read lesson note on Refraction Of Light Through Plane And Curved Surfaces (JAMB)

Refraction Of Light Through Plane And Curved Surfaces

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Question 39 Report

Heat is supplied uniformly at the rate of 100W to 1.0 x 10-2kg of a liquid for 20 seconds. If the temperature of the liquid rises by 5oC, then the specific heat capacity of the liquid is

2.0 x 102Jkg-1k-1

2.0 x 102Jkg-1

4.0 x 104Jkg-1k-1

4.0 x 104kg-1

8.4 x 103Jkg-1k-1

Answer Details

Heat energy = Electrical energy

mc $θ$ = power x time

5 x 1 x 10-2 x C = 100 x 20

C = 4.0 x 104Jkg-1k-1

Read lesson note on Heat Energy (WAEC)

Heat Energy

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Question 40 Report

For correcting long sight defects in the human eye we require a

converging lens

diverging lens

microscope

periscope

plain glass sheet

View Answer

Question 41 Report

Which of the following statements is (are) NOT true about the emission of the photoelectrons from metallic surfaces? i. all metallic surfaces emits the same number of photoelectrons in a given light ii. most metallic surfaces emit the same number of photoelectrons in visible and infra-red light iii. a metallic surface emits photoelectrons only if the frequency of the incident light is higher than its own characteristics threshold frequency

i only

ii only

i and ii

ii and iii

iii only