A water tank appears shallower when it is viewed from top due to:
- (A) Reflection
- (B) Refraction
- (C) Rectilinear propagation of light
- (D) Total internal reflection
- (B) Refraction
Railway tracks are banked on curves so that:
- (A) The weight of the train may be reduced
- (B) Necessary centrifugal force may be obtained from the horizontal component of the weight of the train
- (C) The train may not fall down inward
- (D) No frictional force may be produced between the track and the wheel
- (B) Necessary centrifugal force may be obtained from the horizontal component of the weight of the train
A ship rises as it enters the sea from a river because:
- (A) The seawater is hard
- (B) The larger quantity of water in the sea pushes the ship upward
- (C) The density of seawater is higher than that of the water river
- (D) The density of seawater is lower than that of the water river
- (C) The density of seawater is higher than that of the water river
The sparkling of a diamond is due to:
- (A) Polarization of light
- (B) Total internal reflection of light
- (C) Refraction of light
- (D) Interference of light
- (B) Total internal reflection of light
Small drops of a liquid are spherical in shape because:
- (A) The surface energy is maximum for the spherical shape
- (B) The surface energy is minimum for the spherical shape
- (C) For a given volume, the surface are of a sphere is maximum
- (D) The surface energy remains constant for the spherical shape
- (B) The surface energy is minimum for the spherical shape
Why does radio perception improves slightly during night?
- (A) Sunlight affects radio broadcast to some extent
- (B) The outside noise is reduced very much at night
- (C) The magnetic field of the earth acts with reduced intensity during the night thereby reducing its impact on broadcasts
- (D) The outside noise is increased very much at night
- (A) Sunlight affects radio broadcast to some extent
The reason for a swimming pool to appear less deep than the actual depth is:
- (A) Reflection
- (B) Refraction
- (C) Light scattering
- (D) Interference
- (B) Refraction
The stars twinkle in the night because:
- (A) They emit light intermittently
- (B) The star’s atmosphere absorbs light intermittently
- (C) The refractive index of the air in atmosphere fluctuates
- (D) The earth’s atmosphere absorbs light intermittently
- (C) The refractive index of the air in atmosphere fluctuates
When wind blows at high velocity, roof tops are blown off because pressure:
- (A) Is exerted by air from outside
- (B) Increased due to wind velocity
- (C) Outside is more than inside the roof
- (D) Inside is more than outside the roof
- (D) Inside is more than outside the roof
Starsin the sky appear to twinkle due to:
- (A) A series of refractions
- (B) A series of reflections
- (C) A surface tension phenomenon
- (D) Multiple diminishing brightness
- (A) A series of refractions