Communication Systems
The direction of rotation of a CD is

Clockwise or anticlockwise depending on frequency of data stored
Mostly anticlockwise but some times clockwise
Clockwise
Anticlockwise

ANSWER DOWNLOAD EXAMIANS APP

Communication Systems
Circular polarization

Involves critical alignment of transmitting and receiving antenna
Is useful in reducing depolarization effect on received wave
None of these
Is useful in discrimination between reception of adjacent beams

ANSWER DOWNLOAD EXAMIANS APP

Communication Systems
DVD uses

None of these
Laser beam for recording and video head for playback
Laser beam for both recording and playback
Video head for recording and laser beam for playback

ANSWER DOWNLOAD EXAMIANS APP