How does ice skating work?

Ice skating is definitely fun, and a very popular sport in countries where it is cold in the winter. But how does ice skating work?
Actually we do not slide on the water but on ice, the physics behind this is rather simple: As the friction where the metal blade of the skate touches the ice is very small, it melts the ice locally, and gives the ability to glide. The melted ice will freeze after this immediately

Time travel is possible

A group of young scientists and master students proved in practice that time travel is possible.

Myth of time travel originates long ago in urban legends, but has never been proven before. Also Dougles Adams mentioned similar travels in the trilogy, however those travels were in space.

(Image from http://www.crystalinks.com/timetravel.html)

Why you should not put a cat in the microwave oven

The heating effect of the microwaves comes from the resonance frequency. The wavelengths of the microwave is close to the wavelength, how the water molecules vibrate. And the waves pass small energy packets to the water molecules, speeding up their movement, and this produces heat.

So why is this dangerous for the cat? Read more if you want to know.

(image source: http://www.gifbin.com/981675)

What about free energy?

There are many sites describing and selling "free energy" sources using strong static magnets only. I do not want to bust this myth, and say that a device like that can not work, and can not actually transform energy.  However the sad fact according to the current laws of physic is, that nothing in the world is for absolutely free. Those who claim inventing free energy are stating inventing perpetuum mobile.

The ultimate perpetuum mobile

This joke might reveal what the contradiction of perpetuum mobile is.

The rabbi is asked one day:

- Is it true that if I let fall a slice of bread with butter on the top, it will fall on the side with the butter?

- Yes, answers the rabbi.

- And is it true that if a cat is falling it always falls on the feet?

- Yes.

- So what happens if I let fall a cat standing on the top of the butter bread?

But really, what happens? Let's suppose that both statements are true. Both items should fall on the side where they are glued together. So the answer is simple: it should never fall, and keep flying. And we can say that this is the greatest discovery of all times.

The connection between weather and umbrella

This is somewhat a Murphy theory, but believe me, it is based on many daily observations. The equation is simple:

If you have an umbrella with, that implies no raining that day.

Thus you can influence the weather: if you don't want to have rain, just take the umbrella with :)

Roll or fold in handbag?

With the appearance of low cost airlines nowadays many travelers decide for the easy way of traveling taking only one handbag. To pack a bag for 7 - 10 days is not an easy task, because usually only one hand luggage of limited amount is allowed. There are many different thoughts about what to take and how to organize these items, for example here or here. However there are different ways of thinking about if the clothes should be folded or rolled see for example here. And this is where The Daily Theory comes in. So roll or fold?