A satellite is to be launched into an orbit of radius, r Show that v = 2gr, where V is the launch speed

Explanation:

We start by using the conservation law of energy:

or

Simplifying the above equation, we get

We can rewrite this as

Note that the expression inside the parenthesis is simply the acceleration due to gravity so we can write

where is the launch velocity.

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 =