The heating element often used in an electric iron is
copper
tungsten
mica
nichrome
Correct Answer :
D. nichrome
Related Questions
When are temperature resistance
increases
decreases
remains the same
first increases then decreases
When ice just melts
there is no change in volume
there is no change in temperature
heat is given out
there is no change of state
The overhead wires supported by high towers in the grid system carry
alternating current of very high frequency
alternating current of very high voltage
a very large direct current
a high voltage direct current
We always see only one side of the moon because
the sun comes in between the earth and moon
the moon is stationary
the time taken by the moon to rotate on its axis is the same as the time taken by it to revolve round the earth
moon revolves round the sun
Drinks kept in a vacuum flask remain hot or cold as the case may be for a long time because
both walls are silvered on the vacuum side
there is vacuum between the double walls
the cork is a poor conductor of heat
of all the above
The transistor was invented by
Marconi
Baird
John Bardeen, Walter H. Brattain and William Shockley
Edison
The SI unit of electric current is
the ampere
the volt
the ohm
the coulomb
The line on earth's surface passing through the places having zero dip is called the magnetic equator. This passes through
Thumba
Delhi
Mumbai
Sriharikota
The largest reserve of radioactive element which can be used in a nuclear reactor has been found in India, The name of the element is
Thorium
Uranium
Plutonium
Radium
Less dew is formed on cloudy nights because
there is no moisture in the atmosphere
clouds absorb the falling dew
objects emit radiant energy very fast on such nights
objects lose less radiant energy
We see the sun before it actually rises on the horizon. This is due to
refraction
reflection
total internal reflection
parallax
Meteors
look like falling stars
are really pieces of rock or metal
burn up as they shoot through the air
All the above
The orbit of Venus lies between those of
Mercury and Earth
Earth and Mars
Mars and Saturn
Mars and Jupiter
A stone floor feels cold to the bare feet but a carpet on the same floor feels warm. This is because
the floor and carpet are at different temperatures
the stone conveys the heat away from the feet more rapidly than the carpet
the carpet is a better conductor of heat than the stone
the human body maintains a constant temperature
The loudness of a sound is determined by
Frequency
Amplitude
Speed
Wavelength
The minimum velocity required by a satellite to escape earth's gravitational pull is
18 km/s
11.2 km /s
21 km/s
35 km/s
Sound waves in air are
transverse
longitudinal
transverse and longitudinal
neither transverse nor longitudinal
A transformer
converts direct current into alternating current
converts alternating current into direct current
steps up or steps down a given alternating current voltage
supplies current with zero resistance
Expansion of a rod when heated
is proportional to its original length
is proportional to the increase of temperature
is inversely proportional to its original length
Both (a) and (b) above
A permanent magnet may be demagnetised by
placing it inside a solenoid through which an alternating current is flowing
heating the magnet to redness and then allowing it to cool
dropping it several times or hammering it while lying east-west
All the above
A series of east moving still pictures can be made to appear as a moving picture because the eye
can focus very rapidly as pictures change
is quicker than the brain
can see two images separated only if the interval' between seeing them is more than' one-tenth of a second
can shut out some of the light
When a particle in motion is acted upon by a force in a direction perpendicular to the direction of motion, the path followed by the particle will be
a straight line
an ellipse
a circle
a parabola
Sound waves In 'air travel faster if
frequency is higher
wavelength is smaller
pitch is smaller
air is warmer
The brightest star visible to the naked eye is
Sirius
Vega
Rigel
Proxima Centauri
The barometer was invented by
Michael Faraday
Torricelli
Thomas Alva Edison
Benjamin Franklin
The principle of equivalence of mass and energy was established by
Dalton
Rutherford
Einstein
Planck
If a body is taken from the earth to the moon
both its mass and weight will be different
its mass will be different but the weight will remain the same
its mass and weight will both remain unchanged
its mass will remain the same but weight will be different
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
An astronomical unit of distance is
a kilometre
light year
the average distance from the earth to the sun
None of the above
Sun spots are
the mountains found on the surface of the Sun
the dark patches on the sun having less temperature than the normal sun's surface
ionized gas found near the solar surface
the magnetic storms on the surface of the Sun