Calculate the recombination rate if the excess carrier concentration is 1014cm-3 and the carrier lifetime is 1usec. (a) 108 (b) 1010 (c) 1020 (d) 1014

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

it is given that trillions of microbes make up to 1% to 3% of the body mass.

let's take average of this percentage: 2%

consider the average mass of the human body as 70 kg.

then, trillions of microbes would have mass  

therefore, 100 trillion micro-organisms would weigh:

this is an approximate value and could change depending on the mass of the human body and percentage of the microbes present in it.

average mass per microorganism =