When the pointed end of an uncharged optical pin is brought near the cap cf a positively charged electroscope, it is observed that the gold
Acollapse slowly
Bvibrate
Care not affected
Ddiverge rapidly
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Question 352
waec2011
The capacitance of a parallel-plate capacitor
Adecreases when the seperation between the plate decreases
Bincreases when the optential difference between the plates is increased
Cis greater without a dielectric material between the plates than with a dielectric
Dis greater with a dielectric between the plates than without a dielectric.
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Question 353
waec2011
The correct relationship between "G" and "g" in a gravitational field is given by the equation (Where the symbols have their usual meanings)
Ag = \(\frac{GM}{R}\)
Bg = \(\frac{GM}{R^2}\)
Cg = \(\frac{GM^2}{R}\)
Dg = \(\frac{GM^2}{R^2}\)
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Question 354
waec2011
Which of the following statements about the electromagnetic waves is correct?
Aradio waves have longer frequencies than x-rays
Bx-rays have the longest wavelength
Csome of the waves travel at 3.0 x 108ms-1
Dwhite light occupies a region beyond ultraviolet rays
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Question 355
waec2011
The main difference between echo and reverberation is that
Areverberation is reflected sound while echo is refracted sound
Bthe time interval between incident sound and reflecte sound is shorter for reverbration
Cthe amplitude of an echo is greater
Dreverberation is from acoustic speakers while echo comes from clifts
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Question 356
waec2011
two sound waves have frequencies of 12Hz and 10Hz. Calculate their beats period
A0.5s
B1.0s
C1.2s
D2.0s
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Question 357
waec2011
The focal length of the eye-piece of an astronomical telescope is f1, while the focal length of the object is f2. Fro normal adjustment, the angular magnification is given by
A\(\frac{f_2}{f_1}\)
B1 - \(\frac{f_2}{f_1}\)
C\(\frac{f_2}{f_1}\) - 1
D\(\frac{f_1}{f_2}\)
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Question 358
waec2011
Presbyopia is a defect of the eye resulting from
Aweak ciliary muscles
Bshort eyeball
Closs of sphericity of the lens
Dlong eyeball
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Question 359
waec2011
An object is placed 20.0cm in front of a converging lens of focal length 15.0cm. Calculate its image distance
A1.3cm
B8.6cm
C35.0cm
D60.0cm
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Question 360
waec2011
The speed of light in a certain medium is V while its speed in a vacuum is C. The absolute refractive index of the medium is
AC + V
B\(\frac{C}{V}\)
C\(\frac{V}{C}\)
DC - V
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Question 361
waec2011
Total internal reflection occurs in an optical prism when light rays
Atravel from the prism into an optically denser medium
Bare incident in the prism at an angle greater than the critical angle
Care incident normally in the prism
Dtravel from the prism to the air
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Question 362
waec2011
A ray undergoes a minimum deviation at 40o when it is incident on equilateral triangular glass prism. Calculate the refractive index of the prism
A1.48
B1.50
C1.53
D1.67
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Question 363
waec2011
The image formed by a convex mirror is always
Areal, erect and diminished
Breal, inverted and diminished
Cvirtual, inverted and diminished
Dvirtual, erect and diminshed
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Question 364
waec2011
Which of the following statements about the image formed by a plane mirror is not correct?
Ait is laterally inverted
Bit has unit magnifiation
Cit is formed by actual intersection of rays
Dits distance from the mirror is equal to that of the object from the mirror
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Question 365
waec2011
Ether produces a cooling effect when it is poured on the hand because it has
Alow conductivity
Bhigh conductivity
Chigh latent heat of vaporization
Dlow latent heat of vaporization
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Question 366
waec2011
A metal of mass 200g at a temperature of 100oC is placed in 100g of water at 25oC in a container of negligible heat capacity. If the final steady temperature is 30oC, calculate the specific heat capacity of the metal. [specific heat capacity of the water is 4200 Jkg-1 K-1]
A150 Jkg-1K-1
B300 Jkg-1K-1
C320 Jkg-1K-1
D1960 Jkg-1K-1
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Question 367
waec2011
A body is pulled over a distance of 500m by a force of 20N. If the power developed is o.4 kW, calculate the time interval during which the force is applied
A0.2s
B2.5s
C25.0s
D250.0s
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Question 368
waec2011
Which of the following assumptions is not valid for an ideal gas ?
Amolecules of a particular gas are identical
Bmolecules moves freely throughout the volume of the container
Cforce of attraction between molecules is negligible
Dmolecules move at constant speed between collisions
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Question 369
waec2011
Which of the following statements about anomalous expansion of water are correct? i. There is contraction between 0oC and 4oC. ii. There is expansion between 0oC and 100oC. iii. The volume is minimum at 4oC. iv. The volume is maximum at 4oC
Ai and ii only
Bii and iii only
Ci and iii only
Dii and iv only
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Question 370
waec2011
Which of the following equations shows how how the linear expansivity (\(\alpha\)) and the cubic expansivity (\(\gamma\)) of a material are related?
