Free Fall Acceleration:
Free fall acceleration is the acceleration experienced by an object when it is falling solely under the influence of gravity, with no other forces acting on it, such as air resistance. On Earth, this acceleration is approximately 9.8 m/s2
Relationship Between Gravitational Field Strength and Free Fall Acceleration
The gravitational field strength at any location is numerically equal to the free fall acceleration at that location. This means that an object in free fall will accelerate at a rate equal to the gravitational field strength.
Formula:
g=a
where:
- g is the gravitational field strength,
- a is the acceleration due to gravity (free fall acceleration).
For Earth, g≈9.8 N/kg
Explanation
When an object is in free fall, it is subject to the gravitational force of the Earth, which causes it to accelerate towards the ground. This acceleration is constant and is equal to the gravitational field strength at the location of the fall.
Example
Imagine you drop a stone from a cliff. As it falls, it accelerates towards the Earth due to gravity. This acceleration is approximately 9.8 m/s2 on Earth. This means that every second, the velocity of the stone increases by 9.8 m/s.
Calculating the Velocity of the Stone:
If the stone falls for 3 seconds, its velocity ( v ) can be calculated using the formula:
v=g × t
where:
- V is the velocity,
- g is the acceleration due to gravity (9.8 m/s2)
- t is the time in seconds.
v= 9.8 N/kg × 3s
v=29.4 m/s
So, after 3 seconds, the stone’s velocity will be 29.4 m/s.
The acceleration due to gravity in free fall is independent of the mass of the falling object. This means that objects of different masses, when dropped from the same height in a vacuum, will fall at the same rate.
