5 Fun Physics Phenomena

Have a friend hold a cane horizontally, then try to place your two index fingers underneath the center of mass.

Placing both fingers under the center doesn't normally work when they let go.

• Place each index finger at opposite ends of the cane • Move your fingers toward the middle • They will always end up perfectly under the center of mass • Works even when starting asymmetrically or at different speeds

The mechanics behind this self-correcting behavior remains to be explained.

• Spinning the phone in one direction works easily and stays aligned • Spinning along the short axis also works very well

Flipping the phone end over end cleanly is impossible without it also rotating in another direction.

Even with an almost perfect flip, instabilities grow until the phone rotates around a different axis.

The underlying physics explaining why this middle-axis flip is unstable needs explanation.

Rubbing a cup on hair charges it, and bringing it near a water stream causes deflection. The textbook explanation is that water molecules flip so their positive side faces the negative cup.

In a uniform electric field, equal forces pull the positive side and push the negative side, so molecules only rotate without creating net attraction.

A really strong gradient in the electric field would be needed for this mechanism to work, which a cup cannot produce.

The actual reason why the water stream attracts to a charged cup remains unexplained.

Drop a piece of cereal into a bowl of water and use a very strong magnet to pull it around.

The cereal responds to the magnet and can be moved around in the water.

Why does the cereal exhibit magnetic properties?

The mechanism behind the cereal's magnetism requires additional explanation.

• Cut off the sealed end of a tea bag very carefully • Dump out the tea • Form the tea bag into a square column • Balance it on a plate

Light the top of the tea bag on fire, trying to light it evenly on all sides.

The tea bag rocket launches into the air as the fire burns.

The explanation for why the tea bag launches requires further exploration.

The creator asks viewers to explain these phenomena in the comments or create videos explaining them.

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Commander Chris Hatfield, former commander of the International Space Station, will be hosting live events with the creator in late August in Sydney and Canberra.

Audible offers a free one-month trial with over 150,000 titles. Chris Hatfield's book 'An Astronaut's Guide to Life on Earth' can be accessed via audible.com/veritassium.