A capacitor of 10µF is connected across a cell of 12 volts as shown above, calculate the energy stored in the capacitor
A7.2 x 10-4J
B1.4 x 10-3J
C1.4 x 10-3J
D1.2 x 10-2J
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Question 32
jamb1992
The circuit diagram above contains four ammeters W, X, Y and Z, Which of the following statements about the ammeter readings is correct
AThe reading of W is equal to that of Y and twice that of X
BThe reading of Y is greater than that of Z
CThe readings of W and Y are equal and each is greater than that of X
DThe reading of Z is equal to the sum of the readings of Y and W
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Question 33
jamb1992
The diagram above shows a meter bridge in which two of thee arms contain resistances R and 2Ω. A balance point is obtained at 60cm from the left end , calculate the value of R
A1.2Ω
B1.3Ω
C3.0Ω
D6.0Ω
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Question 34
jamb1992
The diagram above represents the field pattern obtained by bringing the poles of two magnets together.The poles must be
AS-S poles
BS-N poles
CN-S poles
DN-N poles
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Question 35
jamb1992
The fig above shows the heights of two liquids X and Y when some air is sucked out of the apparatus through the pump P. The diameter of the table in X is twice That of the Tube In Y. What is the relative density of the liquid X with respect to liquid Y
A1/3
B2/3
C3
D6
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Question 36
jamb1992
In the diagram above, the hanging mass \(m_2\) is adjusted until \(m_1\) is on the verge of sliding. The coefficient of static friction between the mass \(m_1\) and the table is
Am1/m2
Bm1g/m2
Cm2/m1
Dm2g/m1
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Question 37
jamb1992
A uniform light rod is kept in horizontal equilibrium under the influence of fore forces as shown above, which of the following equations correctly represents the condition of equilibrium for the rod
AF1 + F2 = F3 + F4
BF1 + F2 - F3 + F = 0
C(F1 + F2)ab = (F3 + F4)cd
DF1a + F2b - F3c - F4d = 0
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Question 38
jamb1992
\(^{27}_{13}Al\) + \(^{1}_{0}n\) \(\Rightarrow\) \(^{24}_{11}Na\) + X
Aa proton
Ba gamma ray
Ca helium particle
Dan alpha particle
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Question 39
jamb1992
After three half lifes, the fraction of a radioactive material that has decayed is
A\(\frac{1}{8}\)
B\(\frac{1}{3}\)
C\(\frac{2}{3}\)
D\(\frac{7}{8}\)
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Question 40
jamb1992
The threshold of frequency for photoelectric effect depends on the
Aintensity of incident light
Bfrquency of incident light
Cmaterial of the photocathode
Dpotential difference between the cathode and the anode
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Question 41
jamb1992
In A.C circuit theory, the root means square (r.m.s) current, Irms and the peak (maximum)current Io are related by
AIo = \(\frac{I_rms}{\sqrt{2}}\)
BIrms = \(\frac{I_o}{\sqrt{2}}\)
CIrms = \(\frac{\frac{I}{I_o}}{\sqrt2}\)
DIrms = \(\frac{I_rms}{\sqrt{2}}\)
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Question 42
jamb1992
In alternating current theory, the units of impedance, r.m.s. voltage and resonance frequency are respectively equal to
Avolt, ampere and hertz
Bohms, volt and hertz
Cwatt, ohms and radian
Dohms, hertz and joule
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Question 43
jamb1992
The maximum permissible current through a galvanometer G of internal resistance 10\(\Omega\) is 0.05A. A resistance R is used to convert G into a voltmeter with a maximum reading of 100V. Find the value of R and how it is connected to G
A20,000 ohms in parallel
B19,990 ohms in series
C1990 ohms in series
D100 ohms in series
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Question 44
jamb1992
The heat produced in a conductor carrying an electric current is
Ainversely proportional to the current and the resistance
Bdirectly proportional to the current, resistance and the time
Cinversely proportional to of the resistance, current and the time
Ddirectly proportional to the square of the current, the resistance and the time
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Question 45
jamb1992
Which of the following apparatus will require the smallest fuse rating for its protection?
A60W, 240V
B60W, 40V
C40W, 12V
D40W, 5V
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Question 46
jamb1992
A 5-v battery is connected across the plates of a 2.0\(\mu\)F uncharged parallel plate capacitor. The charge on the capacitor after a long time is
A2.5\(\mu\)C
B10.0\(\mu\)C
C20.0\(\mu\)C
D50.0\(\mu\)C
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Question 47
jamb1992
A wire of length 15m made of a material of resistivity 1.8 x 10-6\(\Omega\)m has a resistance of 0.27\(\Omega\). Determine the area of the wire
A1.5 x 10-4m2
B1.0 x 10-4m2
C2.7 x 10-5m2
D7.3 x 10-6m2
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Question 48
jamb1992
Which of the following factors has no effect on the e.m.f. of a primary cell?
Atemperature
Bsize of the cell
Cnature of the plate
Dnature of the electrolyte
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Question 49
jamb1992
When an ebolite rod is rubbed with fur, it has
Ano charge at all
Ba negative charge
Ca positive charge
Dnegative and positive charges
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Question 50
jamb1992
Calculate the force acting on an electron of charge 1.6 x 10-19C placed in an electric field of intensity 108Vm-1
