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Ah, the stately hot air balloon. Not really useful for all that much except for having a grand old time floating around the skies, it's still a marvel of simple physics. Fill a giant balloon with air.

Yeah, but why does wood float? There are two forces acting on the life jacket - its weight and the force of the water pushing upwards on it - the upthrust. And if the weight is equal to or less than ...

As the Vaihasaya gets close to Venus, the realm of Sukracharya, Meghanth is amazed by its beauty. It looks like a polished crystal ball with a thick atmosphere. Meghnath: Grandpa, Venus looks similar ...

In this sobering, moving drama, a Cambodian teenager runs away from home and is sold into slavery on a Thai fishing boat. By Manohla Dargis When you purchase a ticket for an independently reviewed ...