Understanding the Physics
* Acceleration due to gravity (g): The Earth pulls objects towards it at a constant acceleration of approximately 9.8 m/s². This means the penny's speed increases by 9.8 meters per second every second it falls.
* Initial velocity (v₀): Since the penny was dropped, its initial velocity is 0 m/s.
* Time (t): The time it takes for the penny to fall is 4.5 seconds.
Formula
We can use the following kinematic equation to find the final velocity (v):
v = v₀ + gt
Calculations
1. Plug in the values:
v = 0 m/s + (9.8 m/s²) * (4.5 s)
2. Calculate:
v = 44.1 m/s
Answer
The velocity of the penny when it hits the ground is approximately 44.1 m/s.
