Mixtures can be heterogenous or homogenous
More energy is released in nuclear reactions than in chemical reactions; this is because in nuclear reactions, mass is converted to energy. Nuclear energy released in nuclear fission and fusion is several 100 million times as large as an ordinary chemical reaction like the combustion process. The reason why nuclear energy release so much energy is because tremendous amounts of energy is released at one time. The nuclei in a nuclear reaction undergo a chain reaction, causing the neutrons to move extremely fast and release high amounts of energy.
If the intelligent aliens on that distant planet could receive our signal, and then reply to us INSTANTLY with no delay, then our Scientists on Earth would hear the response <em>eight years after</em> they sent their original greeting.
Light and radio waves both travel through space at the same speed. If our scientists sent a radio transmission to that distant planet, it would take four years for the radio message to get there and be heard. Any response would take four years to travel back to us. If the aliens didn't dilly-dally and sent their response immediately, the round trip would total up to eight years.
Answer:
the correct one is the third :
can travel through a region void of matter and mechanical waves cannot
Explanation:
Mechanical waves travel supported by a material medium, for example sound waves travel in air, the wave on a string travels on the string.
Electromagnetic waves are produced by the variation of electric and magnetic fields, after producing this variation by the lenz law the variation of one field induces the other, so these waves do not need a material medium to travel.
Of the final statements the correct one is the third :
can travel through a region void of matter and mechanical waves cannot