A train with an initial velocity of 20ms-1 is subjected to a uniform deceleration of 2m-2. The time required to bring the train to a complete halt is?
A5s
B10s
C20s
D40s
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Question 432
jamb2013
A simple pendulum of length 0.4m has a period of 2s. What is the period a similar pendulum of length 0.8m at the same place?
A8s
B4s
C2\(\sqrt{2}s\)
D\(\sqrt{2}s\)
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Question 433
jamb2013
The pair of physical quantities that are scalar only are ?
Avolume and area
Bmoment and momentum
Clength and displacement
DImpulse and time
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Question 434
jamb2013
The resultant of two forces is 50N. If the forces are perpendicular to each other and one of them makes an angle 0f 30o with the resultant, find its magnitude.
A100.0N
B57.7N
C43.3N
D25.0N
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Question 435
jamb2013
When a brick is taken from the earth's surface to the moon, its mass
Aremains constant
Breduces
Cincreases
Dbecomes zero
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Question 436
jamb2012
I. Small size.
II. Low power requirement
III. Not easily damaged by high temperature
IV. Highly durable.
Which of the above are the advantages of semiconductors?
AI,II and lll only
Bll,lll and lV only
Cl, II and lV only
Dl, ll, lll and lV
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Question 437
jamb2012
If a reverse-biased voltage is applied across a p-n junction, the depletion layer width is
Aincreased
Bdecreased
Cconstant
Dhalved
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Question 438
jamb2012
The p-n junction diodes can act as rectifiers because they
Aconduct current when forward-biased
Bconduct current when reverse-biased
Cblock current when forward-biased
Dconduct current in both directions
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Question 439
jamb2012
A piece of radioactive material contains 1000 atmos. If its half -life is 20seconds, the time taken for 125 atoms to remain is
A20 seconds
B40 seconds
C80 seconds
D60 seconds
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Question 440
jamb2012
Which of the following CANNOT be deflected by both electric and magnetic fields?
AGamma rays
BAlpha particles
CWave particles
DBeta particles
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Question 441
jamb2012
The process of detecting a pin mistakenly swallowed by a child is X-ray
ADiagnosis
BTherapy
CCrystallography
DMammography
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Question 442
jamb2012
A conductor of length 1m moves with a velocity of 50ms-1 at an angle of 30o to the direction of a uniform magnetic field of flux density 1.5Wbm-2. What is the e.m.f induced in the conductor?
A37.5V
B50.5V
C75.0V
D80.5V
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Question 443
jamb2012
The current output from of an a.c. source is given as I = 10 sin to t. The d.c equivalent of the current is
A5.0A
B7.1A
C10.0A
D14.1A
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Question 444
jamb2012
A particle carrying a charge of 1. 0 x 10-8C enters a magnetic field at 3.0x 10-2 ms -1 at right angles to the field. If the force on this particle is 1.8 x 10-8N, what is the magnitude of the field?
A6.0x10-1T
B6.0x10T
C6.0x10-3T
D6.0x10-4T
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Question 445
jamb2012
The fuse in an electric device is always connected to the
Aneutral side of an electric supply
Bearth side of an electric supply
Clive side of an electric supply
Dterminal side of an electric supply
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Question 446
jamb2012
A newly charged 12V accumulator can easily start a car whereas eight new dry cells in series with a effective e.m.f. of 12V cannot start the same car because
AThe current capacity is high
BThe current capacity is low
Cit cannot be re-charged
Dit cannot easily be connected to a car
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Question 447
jamb2012
Disperson of white light is the ability of white light to
Apenetrate air, water and glass
Bmove in a straight line
Cmove around corners
Dseparate to its component colours
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Question 448
jamb2012
The use of lenses is Not applicable in the
Aprojector
Bhuman eye
Cperiscope
Dtelescope
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Question 449
jamb2012
I. Rays of light travel from a less dense medium to a denser medium. II. The Angle of incidence is greater than critical angle. III. Rays of light travel from a denser medium to a less dense medium. Which of the statements above are conditions for total internal reflection to occur?
AI & II only
BI & III only
CII & III only
DII only
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Question 450
jamb2012
A glass block of thickness 10cm is placed on an object. If an observer views the object vertically, the displacement of the object is
