Why Spheres Spin Differently in Bathtubs & Faucets

In summary, the direction in which a sphere spins in a bathtub or faucet is affected by the Coriolis effect, caused by the Earth's rotation. The shape and size of the sphere can also impact its spin due to differences in mass distribution. The speed at which the sphere is dropped does not affect the Coriolis effect, but other factors such as initial direction of spin and the Bernoulli principle may play a role. The direction of a sphere's spin cannot be controlled due to the complex nature of the Coriolis effect.
  • #1
litotes
9
0
Why does a sphere in a bathtub vortex spin - but a sphere in a faucet remain still ?
 
Physics news on Phys.org
  • #2
The statement is false. The question is: do you have angular momentum? If you leave the water to rest for an hour usually there is no spinning. If you give a little swirl to the water in the sink before you let it out, you can probably force it to start spinning.

Bathtubs have larger dimensions, you a smaller angular momentum of the water is enough. Oh and forget about the Coriolis force. Australian bathtubs are no different than European ones.
 

1. Why do spheres spin in different directions in bathtubs and faucets?

The direction in which a sphere spins in a bathtub or faucet is affected by the Coriolis effect, which is a result of the Earth's rotation. Due to the Earth's rotation, there is a difference in the rotation of fluids in the northern and southern hemispheres. This is why water drains in a clockwise direction in the northern hemisphere and counterclockwise in the southern hemisphere. This effect is too weak to be noticeable in small bodies of water such as bathtubs, but it is more prominent in larger bodies of water such as oceans.

2. Can the shape or size of the sphere affect its spin in a bathtub or faucet?

Yes, the shape and size of a sphere can affect its spin in a bathtub or faucet. The shape and size of a sphere can affect its mass distribution, which can impact the way it interacts with the water currents. A larger or more irregularly-shaped sphere may experience more resistance from the water, causing it to spin in a different direction compared to a smaller or perfectly round sphere.

3. Is there a specific speed at which a sphere must be dropped into a bathtub or faucet for the Coriolis effect to be observed?

No, the speed at which a sphere is dropped into a bathtub or faucet does not affect the Coriolis effect. The Coriolis effect is a result of the Earth's rotation, not the velocity of the sphere. However, other factors such as the shape and size of the sphere, as well as the initial direction of its spin, may impact its behavior in the water.

4. Why do some spheres spin in the same direction as the water flow in a faucet?

In some cases, a sphere may spin in the same direction as the water flow in a faucet due to the Bernoulli principle. This principle states that as the velocity of a fluid increases, its pressure decreases. As water flows out of a faucet, it creates a low-pressure zone around the sphere, causing it to move in the same direction as the water flow. However, the Coriolis effect may still play a role in the overall spin of the sphere.

5. Can the direction of a sphere's spin in a bathtub or faucet be controlled?

No, the direction of a sphere's spin in a bathtub or faucet cannot be controlled. The Coriolis effect is a natural phenomenon that is influenced by many factors, making it difficult to predict or manipulate. Additionally, the effect is too weak to be significant in small bodies of water such as bathtubs, so attempts to control a sphere's spin would likely be unsuccessful.

Similar threads

  • Classical Physics
Replies
8
Views
3K
  • Introductory Physics Homework Help
Replies
15
Views
1K
  • Quantum Physics
Replies
1
Views
226
  • Other Physics Topics
Replies
1
Views
1K
  • Introductory Physics Homework Help
Replies
4
Views
1K
  • Other Physics Topics
Replies
6
Views
3K
  • Introductory Physics Homework Help
Replies
2
Views
477
  • Other Physics Topics
Replies
16
Views
4K
  • High Energy, Nuclear, Particle Physics
Replies
7
Views
508
Replies
1
Views
723
Back
Top