Thick brick walls are used in the construction or a cold storage because bricks
are good conductors of heat
are cheaper
are easily obtained
are bad conductors of heat
Correct Answer :
D. are bad conductors of heat
Related Questions
Echoes are produced by
the reflection of sound waves
the refraction of sound waves
the interference of sound waves
reverberation of sound waves
The attraction between similar molecules is called
inertia
adhesion
cohesion
friction
If you want to open a door with les difficulty you push it
at the middle
at a point away from the hinge (near the rim)
near the hinge
None of the above
The presence of impurities
lowers the melting point of ice
raises the melting point of ice
has no effect on the melting point of ice
may lower or raise the melting point depending upon the type of impurities
The attraction of unlike molecules at the common surface is known as
adhesion
cohesion
surface tension
capillarity
Match the following:
| A. Anemometer | 1. Measurement of power |
| B. Tachometer | 2. Wind speed |
| C. Dynamometer | 3. Revolutions per minute |
| D. Barometer | 4. Atmospheric pressure |
| * | 5. Current from a dynamo |
A-1 B-3 C-5 D-4
A-2 B-1 C-3 D-4
A-2 B-3 C-1 D-4
A-1 B-3 C-5 D-2
No current will flow between two charged bodies if they have the same
resistance
charge
potential
charge/potential ratio
Metals are good conductors of heat because
they contain free electrons
their atoms are relatively far apart
their atoms collide frequently
they have reflecting surfaces
The planet that spins Caster than any other planet is
Saturn
Jupiter
Earth
Mercury
The phenomenon of radioactivity was discovered by
Rutherford
Bohr
Henri Bacquerel
Marie Curie
When a bottle of perfume is opened in one corner of a room the smell spreads soon throughout the room. This is an example of
surface tension
capillarity
viscosity
diffusion
The frequency of an ultrasonic wave is
the same as that of an audible sound
above the audible range
below the audible range
None of the above
The planet that has got a well-developed set of rings is
Venus
Saturn
Mercury
Earth
The largest planet in the solar system is
Neptune
Uranus
Jupiter
Saturn
The focal length or lens or the eye is under the control or the
iris
pupil
ciliary body
cornea
When a charged rod is brought near a collection of small pith balls, the balls
will jump rapidly up and down for a short time
will remain unaffected
Both (a) and (b) above
It will produce electric shock
Powder clings to the skin because of
cohesion
adhesion
capillary action
absorption
The strength of an electromagnet can be increased by
increasing the length of the coiled wire
increasing current supply
increasing the size of the iron core
All the above
Which of the following pairs is not correct?
Television - Baird
Transistor ~ Shockley
Thermometer - Celsius
Barometer Torricelli
An electric fan converts
electrical energy into heat energy
electrical energy into mechanical energy
mechanical energy into electrical energy
mechanical energy into heat energy
Which of the following sets of elementary particles have nearly equal masses?
Neutron and Proton
Electron and Proton
Neutron and Electron
Proton, Neutron and Electron
The number of electrons in the outer orbits of a nucleus gives
the mass number
atomic number
atomic weight
absolute number
The phenomenon of spontaneous disintegration of certain heavy nuclei is termed
radioactivity
fission
fusion
implosion
Which of the following rays has the highest penetrative power?
a -rays
� -rays
? -rays
X-rays
Light from the sun reaches the earth in
2 minutes
4 minutes
12 minutes
8 minutes
The colour of the light which travels through glass with minimum speed is
red
violet
green
yellow
A piece of ice is Boating In water kept in a beaker. When all the ice melts the level of water will
first rise and then fall
fall
remain the same
rise
A light year means
a unit of time
a unit of length
a year of no consequence
illumination throughout the year
Which of the following apparatus is used in the electrolysis of water?
Voltmeter
Voltameter
Ammeter
Potentiometer
A boat loaded with rocks floats in the middle of a swimming pool. A man in the boat throws the rocks overboard. The level of water in the pool will
increase
decrease
remain the same
first decrease and then increase