Answer:
efficiency of a machine is less than 100% because some part is energy is utilized to overcome some opposing forces like friction which is wasted as heat ,sound energy etc
Explanation:
Electromagnetic waves are waves that consist of vibrating electric and magnetic fields. They transfer energy through matter or across space. The transfer of energy by electromagnetic waves is called electromagnetic radiation. ... The two vibrating fields together form an electromagnetic wave.
Answer:
When you have a cloudy night, the clouds prevent heat from escaping through the atmosphere and into space.
The clouds act like a blanket and trap the heat it, and that is why every time you have a cloudy night, it is always warmer than a clear night.