Acar of mass 998 kilograms moving in the positive y–axis at a speed of 20 meters/second collides on ice with another car of mass 1,200 kilograms moving in the negative x direction with a speed of 17 meters/second. after the collision, the cars stick and move together. what is the total momentum in the x direction before the collision?

Momentum in X direction = 20400 kg m/s

Explanation:

As we know that there is no external force on this system of two cars

so here the momentum of two cars will remains conserved always

So here we can say that initial total momentum of two cars in Y direction is given as

Now for X direction total momentum is given as

so here its momentum in x direction will always remains the same and its final momentum in x direction is given as

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 =