Acceleration due to gravity below and above the surface of earth

Any object falling free downward on earth has an acceleration of 9.8 m/s2.

This a numerical value for the acceleration of a free-falling object is very important value therefore it is given a special name as the acceleration of gravity and physicists have a special symbol to denote it - the symbol is g., the acceleration for any object moving under the sole influence of gravity.

There are slight variations in this numerical value in the second decimal place that is dependent primarily upon on altitude.

Some times we use the approximated value of 10 in calculations in order to reduce the complexity of the many mathematical tasks so that we will perform with this number.

The value 10 is taken so that we will be able to better focus on the conceptual nature of physics without too much of a sacrifice in numerical accuracy.

Acceleration Due to Gravity Above and Below Earth Earth Surface Above Earth Surface Gravity decreases with height g becomes smaller as h increases gₕ = g(R / (R+h))² Below Earth Surface Gravity decreases with depth At center of Earth, g = 0 g_d = g(1 - d/R) Center of Earth

Acceleration due to gravity is the acceleration gained by an object due to gravitational force and its SI unit is m/s2.

It has both magnitude and direction, therefore it’s a vector quantity. The Acceleration due to gravity formula is as follows:

v = u + at

s = ut + (1/2)at2

v2 - u2 = 2as

Where,

v = final Velocity

u=initial velocity

a = acceleration

t= time taken

Factors affecting acceleration due to gravity

The shape and rotational motion of the earth

Altitude above the earth's surface and

Depth below the earth's surface.

Comparison Between Gravity Above and Below Earth

Condition                   Effect on g 
--------------------------------------------------
Above Earth’s surface       g decreases gradually  
Below Earth’s surface       g decreases linearly  
At very large height        g becomes very small   
 At Earth’s center          g becomes zero

Frequently Asked Questions

Why does gravity decrease with height?

Because gravitational force decreases as distance from Earth’s center increases.

Why is gravity zero at Earth’s center?

Because Earth pulls equally in all directions at the center.

Is gravity greater on mountain or sea level?

Gravity is slightly greater at sea level because it is closer to Earth’s center.