A 550 N physics student stands on a bathroom scale in an elevator that is supported by a cable. The combined mass of student plus elevator is 840 kg. As the elevator starts moving, the scale reads 430 N. Find the acceleration (magnitude and direction) of the elevator, What is the acceleration is the scale reads 670 N?

(a) The elevator has an acceleration of 2.14 m/s² and direction is downward

(b) The acceleration is a=2.14 m/s²

Explanation:

Let +y be upward direction

For Part (a)

The mass of student (whose weight is 550N) is:

ms=w/g

ms=550/9.8=56.1 kg

Apply ∑Fy=ma

Solve for acceleration a

The elevator has an acceleration of 2.14 m/s² and direction is downward

Part(b)

For the acceleration is the scale reads 670 N

For n=670N

So

higher potential

explanation:

because it is in a high speed so it must move into a of high potential

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 =