Echoes are produced due to _______ of sound.
- (A) Reflection
- (B) Refraction
- (C) Polarization
- (D) Diffraction
- (A) Reflection
Aviation fuel for jet aero-planes consists of purified:
- (A) Diesel
- (B) Petrol
- (C) Kerosene
- (D) Gasoline
- (C) Kerosene
In the process of galvanization an iron sheet is coated with:
- (A) Silicon
- (B) Zinc
- (C) Tin
- (D) Aluminum
- (B) Zinc
Very High Frequency (VHF) has _______ wavelengths.
- (A) Shorter
- (B) Shortest
- (C) Longer
- (D) Longest
- (A) Shorter
When light enters from rare to denser medium, it bends towards the normal line, it is called:
- (A) Reflection of light
- (B) Refraction of light
- (C) Diffraction of light
- (D) Absorption of light
- (B) Refraction of light
“Mirage” is an example of:
- (A) Reflection of light
- (B) Refraction of light
- (C) Deviation of light
- (D) Polarization of light
- (B) Refraction of light
The functioning of a ‘Loudspeaker’ depends upon its:
- (A) Size
- (B) Shape
- (C) Size and Shape
- (D) None of these
- (C) Size and Shape
Aviation fuel for jet aero-planes consists of purified:
- (A) Petrol
- (B) Diesel
- (C) Gasoline
- (D) Kerosene
- (D) Kerosene
What are primary colors?
- (A) Colors found in nature
- (B) Colors of the rainbow
- (C) Colors which cannot be produced
- (D) Colors in the spectrum of white light
- (C) Colors which cannot be produced
A color television set makes colors by mixing light of which three different colors?
- (A) Blue, Green and Yellow
- (B) Red, Green and Blue
- (C) Green, Black and Red
- (D) Red, Blue and Brown
- (B) Red, Green and Blue