Drop a ball from a rooftop. It doesn't fall at a constant speed — it speeds up every second. This continuous speeding up is caused by Earth's gravity, and the rate at which it speeds up is a fundamental constant called the Acceleration of Free Fall.
On the Moon, the acceleration of free fall is only 1.6 m/s² — about 1/6th of Earth's — which is why astronauts bounce slowly and can jump very high!
The Acceleration of Free Fall (also called Acceleration due to Gravity, denoted g) is the constant acceleration experienced by any object falling freely under the influence of Earth's gravity alone, with no other forces acting on it (no air resistance).
Value: g = 9.8 m/s² (approximately 10 m/s² for quick calculations)
Every single second an object is in free fall, its downward speed increases by 9.8 meters per second.
Using kinematic equations with a = g = 9.8 m/s² and initial velocity u = 0:
**No!** Galileo proved that in the absence of air resistance, all objects fall with the same acceleration (g = 9.8 m/s²) regardless of their mass. A feather and a hammer dropped in a vacuum hit the ground simultaneously.
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