Common Observations

Sunlight affects radio broadcast to some extent

The outside noise is reduced very much at night

The magnetic field of the earth acts with reduced intensity during the night thereby reducing its impact on broadcasts

None of these

Metal is poor conductor of heat

The expansion of the glass after heating is uniform and therefore it cracks

Glass is poor conductor of heat

In case of glass, the heat is transmitted quickly when it is heated

It increases boiling point of water

It increases the temperature of the content

Of the penetrating action of steam

The whole of the heart remains inside

Sky is made up of blue colour particles

Blue color of light is of shorter wavelength, so these waves are easily scattered by dust particles and water vapour

Blue colour is more prominent in sunlight

Blue colour is of longer wavelength

Interference

Diffraction

Polarisation

Refraction

Sea water is still while river water in running

Salinity of seawater is more than that of river water

Density of seawater is more than that of river

None of these

The atmosphere absorbs short wavelengths more than long wavelengths.

High of shorter wavelengths are a scattered to a greater extent than the longer wavelengths by the atmosphere

The atmosphere absorbs long wavelengths more than short wave lengths

None of these

Sea animals are salt producing

Rivers wash away salts from earth and pour them into sea

Sea beds have salt producing mines

The air around sea is saltish

The train may not fall down inward

Necessary centrifugal force may be obtained from the horizontal component of the weight of the train

No frictional force may be produced between the track and the wheel

The weight of the train may be reduced

Conduction

Radiation

Condensation

Insolation