Physics Questions

Sound intensity is measured in decibels(db). Sound pollution above 120 db becomes more hazardous and have adverse affects on human life. 

Weight is mass x g. Since mass is constant and g is only 16thof that on the earth. The weight on the moon is only 16th of that on the earth. 

Therefore 2N i.e (b) is the answer.

Microwaves are high-frequency signals in the 300 MHz to 300 GHz range. This is in contrast to radio signals, which are typically broadcast in all directions. Radio signals operate in the 3 Hz to 300 MHz range.

Microwave signals are used for both satellite and ground-based communications.

Quality of transmission is governed both by nature of signal and nature of communication channel/medium.

Entropy is a measure of disorder . It will be maximum in gases followed by liquids and least in solids.

Hence, here the gas is only hydrogen and it has the highest entropy.