Answer:
light waves can travel in vacuum but sound waves require a medium to travel
also light waves are electromagnetic waves while sound waves are mechanical, light waves are transverse waves while sound waves are longitudinal waves
An example is free fall ,
Efficiency = 45J/120J = 0.375
Or
0.375 * 100% = 37.5 %
Heat always flows from a B. hotter object to a colder one.
Heat transfers always from hotter to colder.
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