Polarization and interference
Diffraction and dispersion
Multiple refraction and dispersion
Multiple reflection and interference
The ink of a pen leaks out in an airplane because
The inside of a photographic camera is coated black to avoid
The instrument for measuring intensity of earthquakes is called
The instrument used in aircrafts to measure the altitude above a fixed level is:
The instrument used to measure the speed of the wind is
The instrument which uses sound waves to measure the depth of oceans is
The insulation resistance of cables, transformers etc is measured by following instrument
The intensity of sound at a point is _ its distance from the source
The intensity ratio of waves is 25 : 9. What is the ratio of their amplitudes?
The internal resistance of all milliammeter must be very low for