The diagram above shows the velocity-time graph of a vehicle. Its acceleration and retardation respectively are
A8.0 ms-2, 4,0 ms-2
B4.0 ms-2, 8.0 ms-2
C4.0 ms-2, 2.0 ms-2
D2.0 ms-2, 4.0 ms-2
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Question 32
jamb1999
If ∆x is the uncertainty in the measurement of the position of a particle along the x-axis and ∆Pa is the uncertainty in the measurement of the linear momentum along the x-axis, then the uncertainty principle relation is given as
A∆x ∆Px ≥ h
B∆x ∆Px = 0
C∆x ∆Px < h
D∆x ∆Px = ∞
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Question 33
jamb1999
if ∆x is the uncertainty in the measurement of the position of a particle along the x-axis and ∆Px is the uncertainty in the measurement of the linear momentum along the x-axis, then the uncertainty principle relation is given as
A∆x ∆Px ≥ h
B∆x ∆Px = 0
C∆x ∆Px < h
D∆x ∆Px = ∞
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Question 34
jamb1999
A semiconductor diode is used in rectifying alternating current into direct current mainly because it
Aallows current to flow in either direction
Bis non-linear
Coffers a high input resistance
Dallows current to flow only in one direction
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Question 35
jamb1999
2311Na + Proton → pqX + alpha particle
What are the values of p and q respectively in the equation above?
A10 and 20
B12 and 24
C20 and 10
D24 and 12
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Question 36
jamb1999
In the Rutherford scattering experiment, a beam of alpha particles was fired at a thin gold film with some of the particles being considerably deflected. This shows that
Aa gold nucleus contains protons, neutrons and electrons uniformly distributed in a tiny volume
Bthe gold nucleus is positively charged and is concentrated in a tiny volume
Cthe gold nucleus emitted alpha particles
Dthe gold nucleus is concentrated in a tiny volume and contains alpha particles
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Question 37
jamb1999
in a series R-L-C circuit at resonance, the voltages across the resistor and the inductor are 30V and 40V respectively, what is the voltage across the capacitor?
A30V
B40V
C50V
D70V
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Question 38
jamb1999
What is the speed of a particle of mass 10-27kg whose wavelength is 10-8m.
[h = 6.63 x 10-34Js]
A6.63ms-1
B66.30ms-1
C663.00ms-1
D6630.00ms-1
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Question 39
jamb1999
Gamma rays are produced when
Ahigh velocity electrons are abruptly stopped in metals
Benergy changes occur within the nucleus of atoms
Cenergy changes occur within the electronic structure of atoms
Delectrons are deflected in very strong magnetic fields
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Question 40
jamb1999
The core of an efficient transformer should consist of laminated pieces of metal in order to
Aincrease the heat produced by increasing the eddy current
Bincrease the heat produced by reducing the eddy current
Creduce the heat produced by increasing the eddy current
Dreduce the heat produced by reducing the eddy current
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Question 41
jamb1999
At what frequency would a 10H inductor have a reactance of 2000Ω?
Aπ/200Hz
Bπ/100Hz
C100/πHz
D100πHz
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Question 42
jamb1999
In fleming's right-hand rule, the thumb, the forefinger and the middle finger if held mutually at right angles represent respectively, the
Amotion, the field and the induced current
Binduced current, the motion and the field
Cfield, the induced current and the motion
Dinduced current, the field and the motion
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Question 43
jamb1999
A galvanometer has a resistance of 5Ω. By using a shunt wire of resistance 0.05Ω, the galvanometer could be converted to an ammeter capable of reading 2Amp. What is the current through the galvanometer?
A2mA
B10mA
C20mA
D25mA
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Question 44
jamb1999
A 3000W electric cooker is to be used on a 200V mains circuit. Which of the fuses below can be used safely with the cooker?
A2A
B5A
C10A
D20A
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Question 45
jamb1999
Four cells each of e.m.f 1.5V and internal resistance of 4Ω are connected in parallel. What is the effective e.m.f. and internal resistance of the combination?
A6.0V, 16Ω
B6.0V, 1Ω
C1.5V, 4Ω
D1.5V, 1Ω
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Question 46
jamb1999
Steel is more suitable for permanent magnet than iron because the former
Ais easily demagnetized by shaing vigorously
Bis an alloy of many metals
Cis easily magnetized by alternating current through one cycle
Dretains magnetism more than iron
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Question 47
jamb1999
Which of the following electromagnetic waves is least energetic?
AInfra-red rays
BX-rays
CUltra-violet rays
DGamma rays
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Question 48
jamb1999
An astronomical telescope is said to be in normal adjustment when the
Aeye is accommodated
Bfocal length of objective lens is longer than that of eye piece
Cfinal image is at the near point of eye
Dfinal image is at infinity
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Question 49
jamb1999
The velocities of light in air and glass are 3.0 x 108ms-1 and 2.0 x 108ms-1 respectively. If the angle of refraction is 30°, the sine of the angle of incidence is
A0.33
B0.50
C0.67
D0.75
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Question 50
jamb1999
The inside portion of part of a hollow metal sphere of diameter 20cm is polished. The portion will therefore form a
