20000.It is easier to roll a stone up a sloping road than to lift it vertical upwards because
work done in rolling is more than in lifting
work done in lifting the stone is equal to rolling it
work done in both is same but the rate of doing work is less in rolling
work done in rolling a stone is less than in lifting it
20010.Rectifiers are used to convert
Direct current to Alternating current
Alternating current to Direct current
high voltage to low voltage
low voltage to high voltage
20020.Materials for rain-proof coats and tents owe their water-proof properties to
surface tension
viscosity
specific gravity
elasticity
20036.Railway tracks are banked on curves
necessary centrifugal force may be obtained from the horizontal component weight of the train
to avoid frictional force between the tracks and wheels
necessary centripetal force may be obtained from the horizontal component of the weight of the train
the train may not fly off in the opposite direction
20024.Suitable impurities are added to a semiconductor depending on its use. This is done in order to
increase its life
enable it to withstand higher voltages
increase its electrical conductivity
increase its electrical resistivity
20060.Large astronomical telescopes always use as objective
lens
mirror
combinations of lenses
None of the above
20021.RADAR is used for
locating submerged submarines
receiving a signals in a radio receiver
locating geostationary satellites
detecting and locating the position of objects such as aeroplanes
20030.Sound travels with a different speed in media. In what order does the velocity of sound increase in these media?
Water, iron and air
Iron, air and water
Air, water and iron
Iron, water and air
20006.Let a thin capillary tube be replaced with another tube of insufficient length then, we find water
will overflow
will not rise
depressed
change its meniscus
20061.One should not connect a number of electrical appliances to the same power socket because
this can damage the appliances due to overloading
this can damage the domestic wiring due to overloading
this can damage the electrical meter
the appliance will not get full voltage
20007.Out of the following pairs, choose the pair in which the physical quantities do not have identical dimension?
Pressure and Youngs modules
Plancks constant and Angular momentum
Impulse and moment of force
Force and rate of change of linear momentum
20018.On a rainy day, small oil films on water show brilliant colours. This is due to
dispersion
interference
diffraction
polarization
20023.On a clean glass plate a drop of water spreads to form a thin layer whereas a drop of mercury remains almost spherical because
mercury is a metal
density of mercury is greater than that of water
cohesion of mercury is greater than its adhesion with glass
cohesion of water is greater than its adhesion with glass
20033.oil raise up the wick in a lamp. The principle involves
the diffusion of oil through the wick
the liquid state of oil
capillary action phenomenon
volatility of oil
20041.Radio telescopes are better than optical telescopes because
they can detect faint galaxies which no optical telescope can
they can work even in cloudy conditions
they can work during the day and night
All of the above