When we tighten the string of a sitar or tanpura its pitch
remains the same
increases
decreases
None of the above
Correct Answer :
B. increases
Related Questions
Holography is the technique of
taking photos of various objects
recording and reproducing three dimensional images
tracing out planets and stars in the sky
transmitting light waves
The principle on which a Jet engine works is
conservation of mass
Newtonian law of action and reaction
conservation of angular momentum
None of the above
SONAR (Sound Navigation Ranging) is
used by warships and military aircraft to locate enemy submarines
used by ships to determine the depth of water beneath them
a detective device that uses sound to locate under - water objects
All the above
Velocity of sound in high altitudes is low because at such a height
the temperature is low
there is no air
the pressure is low
All the above
The ringing of an electric bell in an enclosed evacuated glass bell jar is not heard outside because
the ringing is not loud enough
the glass of the bell jar absorbs the sound waves
the bell jar is too small
there is no air or -any other gas in the bell jar
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 radius of curvature of a spherical mirror is
equal to half its focal length
equal to its focal length
twice its focal length
not related to its focal length
The speed of sound in air at 0° C is approximately
4 x 10 8 m/s
1500 m/s
330 m/s
500 m/s
Mercury is used in thermometers because
it has high thermal conductivity
it has uniform expansivity
it has high boiling point and low freezing point
of all the above
Which force is used when milk is churned to separate cream?
cohesive
centrifugal
frictional
gravitational
The red colour of the setting sun is due to
the least scattered red colour reaching the eye
the dispersion of sun light occurred in air molecule in atmosphere
the diffraction of sunrays in atmospheric layers
interference of all the rays coming from the sun
Before the invention of geostationary satellites, television stations could not transmit their programmes to far off places because
these signals are electromagnetic in nature
these are not electromagnetic in nature
their wavelength is very large
they are not reflected by the ionosphere but pass through it
The maximum range of most TV signals is from 121 to 240 km only because
the curvature of earth limits the range of reception
the signals are weak
the signals are absorbed by air
the antennae are not powerful enough
Where does the centre of gravity of a rubber ring lie?
on the outer surface
in the inner surface
at the centre of the ring
None of the above
When a body is partly or wholly immersed in a liquid the apparent loss of weight is equal to the weight of the liquid displaced by the submerged portion. This is known as
Pascal's law
Bernoulli's law
Archimedes' law
Boyle's law
The phenomenon of spontaneous disintegration of certain heavy nuclei is termed
radioactivity
fission
fusion
implosion
A pressure gauge for fluids is called
a hydrometer
a manometer
a lactometer
an anemometer
For viewing objects placed at a higher level from a position at a lower level, the instrument used' Is known aa
telescope
spectrometer
microscope
periscope
Skating on ice is possible because
the surface of ice is smooth
ice is cold
the pressure on the ice due to skate melts the ice by lowering its melting point forming a thin film of water
the pressure on the ice due to skate raises its melting point
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
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
The stem of a vibrating tuning fork is pressed against a sound box. Then
the loudness of the sound increases
the loudness remains the same
the loudness decreases
the sound suddenly stops
Out of the following, name the fluorescent substance.
quinine sulphate solution
paraffin oil
fluorescein solutions
All the above
The planet that has got a well-developed set of rings is
Venus
Saturn
Mercury
Earth
Holography is the technique of
taking photos of various objects
recording and reproducing three dimensional images
tracing out planets and stars in the sky
transmitting light waves
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
A ship sailing from a river to the sea
sinks less in the sea
sinks more in the sea
neither sinks more nor less in the sea
sinking more or less depends on sea
The ozone layer absorbs
Cosmic rays
Infrared rays
All radiations of light
Ultra violet rays coming from the sun
When the earth reaches its perihelion
it is nearest to the moon
it is nearest to the sun
it is nearest to Pluto
it is farthest from the sun
A lightning conductor installed in a building
does not allow the lightning to fall on the building at all
drives away the charged clouds
forces the lightning to fall on other buildings near that building
conducts the electric charges to the ground when lightning strikes the building