Kinetic energy has nothing to do with anything other than motion of the particle.
When a particle with velocity v collides another particle(suppose it is at rest for simplication), assuming that there is perfectly elastic collision between them, the velocity of particle which was at rest becomes mv/M ( assuming mass of particle in motion to be m and at rest to be M) from convervation of linear momentum. And all this transfer of energy happens in a fraction of seconds which is not visible to naked eyes.
Hence 1st option is correct!
B is the right answer. Multiply numbers you get the answer
Answer:
Living Things
Explanation:
Physical science is the study of the inorganic world. That is, it does not study living things. (Those are studied in biological, or life, science.) The four main branches of physical science are astronomy, physics, chemistry, and the Earth sciences, which include meteorology and geology.
Answer:

Explanation:
The recombination rate is denoted by R it is the ratio of excess carrier concentration and life time
The recombination rate R is given by 
We have given excess carrier concentration = 
Life time 
So recombination rate 