Newton's Law of Universal Gravitation
* Force of Gravity: The force of gravity acts on all objects with mass. This force is proportional to the mass of the object and the mass of the Earth.
* Acceleration due to Gravity (g): Since the force of gravity is the only force acting on the objects in a vacuum, their acceleration is solely determined by the gravitational force. This acceleration is constant near the Earth's surface and is approximately 9.8 m/s².
The Role of Air Resistance
* Air Resistance: In normal conditions, air resistance significantly affects the motion of objects. A feather, with its large surface area, experiences much greater air resistance than a coin. This causes the feather to fall much slower.
* Vacuum Elimination: A vacuum tube eliminates air resistance. There's no air to slow the feather down.
Conclusion:
In a vacuum, both the coin and the feather experience the same gravitational force. Since there is no air resistance to impede their motion, they both accelerate at the same rate – the acceleration due to gravity (g). This means they will fall at the same speed and reach the bottom of the tube simultaneously.
