In a compound microscope, the objective and the eye piece focal lengths are
AAt infinity
BLong
CShort
DThe same
View Explanation & Discuss
Question 702
jamb2014
The focal length of a concave mirror is 2.0cm. If an object is placed 8.0cm from it, the image is at
A2.7m
B2.0m
C2.3m
D2.5m
View Explanation & Discuss
Question 703
jamb2014
An object is placed 10m from a pinhole camera of length 25cm. Calculate the linear magnification.
A2.5x102
B2.5x10-2
C2.5x10-1
D2.5x101
View Explanation & Discuss
Question 704
jamb2014
A boy receives the echo of his clap reflected by a nearby hill 0.8s later. How far is he from the hill? [ speed of sound in air = \(340ms^{-1}\)
A528m
B66m
C136m
D264m
View Explanation & Discuss
Question 705
jamb2014
The distance between two successive crests of a wave is 15cm and the velocity 300ms-1. Calculate the frequency.
A2.0x102Hz
B4.5x103Hz
C2.0x103Hz
D4.5x102Hz
View Explanation & Discuss
Question 706
jamb2014
Heat transfer by convection in a liquid is due to the
ALatent heat of vaporization of the liquid
BIncreased vibration of the molecules of the liquid about theit mean position
CVariation of density of the liquid
DExpansion of the liquid as it is heated
View Explanation & Discuss
Question 707
jamb2014
The temperature at which the water vapour present in the air is just sufficient to saturate air is
ABoiling point
BIce point
CSaturation point
DDew point
View Explanation & Discuss
Question 708
jamb2014
The melting point of a substance is equivalent to its
AVapour Pressure
BSolidification Temperature
CLiquidification Temperature
DSolidification Pressures
View Explanation & Discuss
Question 709
jamb2014
The quantity of heat needed to raise the temperature of a body by 1K is the body's
AHeat capacity
BInternal energy
CSpecific heat capacity
DLatent heat of fusion
View Explanation & Discuss
Question 710
jamb2014
The equation PaVbTc= constant reduces to Charles Law if
Aa=1, b=1and c=0
Ba=1, b=0 and c=-1
Ca=0, b=1 and c=1
Da=0, b=1 and c=-1
View Explanation & Discuss
Question 711
jamb2014
What is the equivalent of 20K in Celsius scale?
A-253oC
B-293oC
C68oC
D36oC
View Explanation & Discuss
Question 712
jamb2014
The small droplets of water that form on the grass in the early hours of the morning is
AFog
BHaul
CMist
DDew
View Explanation & Discuss
Question 713
jamb2014
A force of 500N1 is applied to a steel wire of cross-sectional area 0.2m2, The tensile stress is
A2.5x104Nm-2
B1.0x102Nm-2
C1.0x103Nm-2
D2.5x103Nm-2
View Explanation & Discuss
Question 714
jamb2014
A wheel and an axle is used to raise a load whose weight is 800N when an effort of 250N is applied. If the radii of the wheel and axle are 800mm and 200mm respectively, the efficiency of the machine is
A90%
B80%
C85%
D87%
View Explanation & Discuss
Question 715
jamb2014
A machine whose efficiency is 75% is used to lift a load of 1000N. Calculate the effort put in to the machine if it has a Velocity ratio of 4.
A343.32N
B233.33N
C333.33N
D334.33N
View Explanation & Discuss
Question 716
jamb2014
The energy in the nucleus of atoms produce heat which can be used to generate
AKinetic energy
BMechanical energy
CElectrical energy
DPotential energy
View Explanation & Discuss
Question 717
jamb2014
An object of mass 20kg is released from a height of 10m above the ground level. The kinetic energy of the object just before it hits the ground is
A200J
B4000J
C2000J
D500J
View Explanation & Discuss
Question 718
jamb2014
What happens when three coplanar non-parallel forces are in equilibrium?
ATheir lines of action are parallel.
BThey are represented in magnitude only
CThey are represented in direction only
DTheir lines of action meet at a point
View Explanation & Discuss
Question 719
jamb2014
One of the conditions necessary for an object to be in equilibrium when acted upon by a number of parallel forces is that the vector sum of the forces is
AAverage
BZero
CNegative
DPositive
View Explanation & Discuss
Question 720
jamb2014
An object of weight 8kg on earth is taken to a planet where acceleration due to gravity is one-third of its value on earth. The weight of the object on the planet is
