Segments in this Video

Does Water Always Drain in a Clockwise Direction? (04:25)


Some people say that the Coriolis effect is far too small to be measured with small bodies of water and that if we do see any swirling, it has more to do with either the shape of the container or with the movement that the water already had before it started draining.

The Theory of the Coriolis Effect (01:57)

The Coriolis effect is the apparent deflection of objects in motion due to the Earth's rotation. It is responsible for the rotation of hurricanes in the northern hemisphere and the counter-clockwise rotation of water draining from a container in the northern hemisphere.

How Does the Coriolis Effect Work? (02:13)

The Coriolis effect is the apparent shifting of an object's movement due to the Earth's rotation. In the Northern Hemisphere, the theory is that water should drain and that winds will flow in cyclones in an anti clockwise spiral. But if you're in the Southern Hemisphere, it is the opposite because you're kind of upside down with respect to the Northern Hemisphere.

Tropical Cyclones (02:57)

Tropical cyclones form over warm tropical waters and usually move from east to west initially. They are caused by the uneven heating of the Earth's surface, and the warm air in the low pressure region rises. The air is deflected and starts to rotate because of the spinning of the Earth and the Coriolis effect.

Winds and the Coriolis Effect (03:41)

A tropical cyclone is a low pressure system with very strong winds. The winds are especially ferocious near the center of the cyclone, which is called the eye.

Experiment: Draining Water (03:08)

The Coriolis effect is a force that affects the direction in which water drains out of a container. It is caused by the Earth's rotation. In the Southern Hemisphere, water drains clockwise. In the Northern Hemisphere, water drains anticlockwise. Near the equator, the Coriolis effect is very small and does not seem to affect the direction of water drainage.

Tropical Storms and Cyclones (03:14)

The Coriolis effect does not have a significant effect near the equator. Tropical cyclones rotate in different directions in the two hemispheres. The biggest difference between the Northern and Southern Hemispheres is the temperature difference between summer and winter.

Credits (00:20)


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Episode 4: The Coriolis Effect

Part of the Series : Shedding Light on the Sun and Earth
DVD (Chaptered) Price: $99.95
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In this episode, we describe how tropical cyclones form and examine their huge power. We explain what the Coriolis Effect is and how it makes tropical cyclones rotate the way that they do. We also travel to three continents to demonstrate how the Coriolis Effect affects water draining from a small container. Does water really swirl in a different direction depending on which hemisphere it’s in?

Length: 24 minutes

Item#: BVL206386

ISBN: 978-1-64867-731-1

Copyright date: ©2020

Closed Captioned

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