How Do You Calculate Acceleration and Distance of a Free-Falling Object?

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jsm6252
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my question leads to something bigger but to start g force on Earth is 9.8m/s2 for simlicity let's say 10.

1-is it rite to say if you drop an object in the 1st sec its acceleration is 10m/s2 in the 2nd sec it's 100m/s then in the 3rd sec it's 10000 m/s
2-if the above is correct what is the distance traveled i.e in the 3rd sec has the object traveled a total of 10000m.
3-how do you calculate g 100km above the earth.
 
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jsm6252 said:
1-is it rite to say if you drop an object in the 1st sec its acceleration is 10m/s2 in the 2nd sec it's 100m/s then in the 3rd sec it's 10000 m/s

No. After one second, its velocity is 10 m/s, after two seconds its velocity is 20 m/s, after three seconds its velocity is 30 m/s, etc. Its acceleration remains constant at 10 m/s^2.
 
To calculate g at 100km you need to use the equation:

g = (G*m1*m2) / r2

Where G is the gravitational constant, m1 is the mass of the earth, m2 is the mass of the body currently at 100km, r2 is the distance from the centre of the Earth (Earth's radius plus altitude of 100km).
 
A quicker way to calculate g at a given altitude h is to use the relation:

g at h = g at sea level * (r Earth / (r Earth + altitude))^2

where r Earth = average radius of the earth.

The quantity G * m1 * m2 / r^2 is the gravitational force acting between two masses m1 and m2 which are a distance r apart.