A girl standing some distance from the cliff claps her hands and hears the echo 0.8s later. calculate her distance from the cliff. [speed of sound in air = 320 ms-1]
A23m
B128m
C288m
D298m
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Question 12
waec2015
When an air column is set into vibrations, the distance between two consecutive nodes of the resultant wave is
Aone quarter of the wavelength
Bhalf of the wavelength
Cthe wavelength
Dtwice the wavelength
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Question 13
waec2015
A swimming pool is 2.1m deep. If it contains water of refractive index 1.3, calculate the apparent depth of pool
A3.4m
B2.7m
C1.6m
D0.8m
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Question 14
waec2015
An object is placed 15cm from a diverging lens of focal length 12cm. The image of the object formed by the lens in
Areal and 6.67cm from the lens
Bvirtual and 6.67cm from the lens
Creal and 60.00cm from the lens
Dvirtual and 60.00cm from the lens
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Question 15
waec2015
What type of wave is emitted by a loud speaker?
ATransverse
BLongitudinal
CGamma
DRadio
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Question 16
waec2015
The diagram given illustrates a wave form. Determine the speed of the wave
A5.4 ms-1
B8.4 ms-1
C9.6 ms-1
D10.0 ms-1
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Question 17
waec2015
The pressure applied to an enclosed fluid to one end id transmitted equally throughout the fluid and to the container walls. This statement is
AArchimede's principle
BBernoulli's principle
CPascal's principle Heisenberg's
DHeisenberg's uncertainty principle
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Question 18
waec2015
Which of the following units is the S.I. unit of heat capacity?
AJkg-1
BJkg-1 K-1
CJK-1
DJg-1K-1
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Question 19
waec2015
Which of the following concepts is a method of heat transfer that does not require a material medium?
Aconduction
Bradiation
Cdiffusion
Dconvection
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Question 20
waec2015
In an experiment in which a molten substance is allowed to cool, the cooling curve above was obtained. The temperature 60oC is known as the
Avaporization point
Bcooling temperature
Cboiling point
Dmelting point
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Question 21
waec2015
In an experiment in which a molten substance is allowed to cool, the cooling curve above was obtained. The temperature 60oC is known as the
Avaporization point
Bcooling temperature
Cboiling point
Dmelting point
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Question 22
waec2015
A battery of emf 24V is connected to three resistor P, Q and R as illustrated in the diagram. Determine the voltage across the resistor Q
A5v
B10v
C14v
D24v
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Question 23
waec2015
A quantity of hot water at 100oC is added to 400g of water at 10oC until the temperature of the mixture is 60oC.
Calculate the mass of the hot water added. [Specific heat capacity of water =4200JKg-1 K-1]
A200g
B320g
C400g
D500g
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Question 24
waec2015
The diagram above illustrates a block ans tackle pulley system in which an effort E supports a load of 100.0N. If the efficiency of the machine is 75%, calculate the value of E
A22.2N
B38.0N
C67.0N
D75.0N
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Question 25
waec2015
Water is unsuitable for use as a thermometric liquid because it
Aexpands unevenly between 0oC and 40oC
Bhas narrow temperature range
Chas a concave meniscus
Dmaintains a fixed density
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Question 26
waec2015
The crackling noise produced by aluminum roofing sheets on a house during a hot sunny day is a result of
Athermal equilibrium of the sheets
Bconduction of heat by the sheets
Ccontraction of the sheets
Dexpansion of the sheets
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Question 27
waec2015
A body of mass 1000kg is released from a height of 10m above the ground. Determine its kinetic energy just before it strikes the ground .[g = 10ms-2]
A10J
B103J
C104J
D105J
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Question 28
waec2015
A uniform bar AB is balanced on a knife-edge which is 60cm from B by a mass of 22g which hangs at C 10cm from A. Calculate the mass of the bar.
A133.2g
B66.0g
C60.0g
D22.0g
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Question 29
waec2015
A bullet fired vertically upwards reaches a height of 500m. Neglecting air resistance, calculate the magnitude of the initial velocity of the bullet. [g = 10ms-2]
A500.0ms-1
B100.0ms-1
C70.0ms-1
D50.0ms-1
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Question 30
waec2015
Two strings each inclined at an angle 30o to the horizontal are used to hold a bucket of water weighing 20N. Calculate the tension i n each string.
