Raindrops fall due to gravity, but their journey and shape change as they descend through the atmosphere.
Initially, high in the atmosphere, raindrops form as spherical droplets. This is because water molecules bind together, held by surface tension. As they fall, several factors influence their shape and motion:
- Collision: Raindrops collide with other raindrops, increasing their size.
- Air Resistance: Air resistance plays a crucial role. As a raindrop accelerates downwards, the force of air resistance pushing upwards increases. This force eventually balances with the force of gravity, at which point the raindrop reaches its terminal velocity.
- Shape Change: The shape of the raindrop is also affected by air resistance. Instead of remaining perfectly spherical, air resistance causes the bottom of the drop to flatten and curve, resembling the shape of a jelly bean. Larger raindrops become more flattened and unstable.
Here's a table summarizing the changes in raindrop shape during their fall:
| Stage | Shape | Reason |
|---|---|---|
| Initial Formation | Spherical | Surface tension between water molecules |
| During Fall | Jelly Bean-like | Air resistance flattens the bottom of the drop |
Therefore, raindrops don't fall as teardrop-shaped entities as commonly depicted, but rather more like flattened spheres or jelly beans due to air resistance.
