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Science

What is Buoyancy?

Buoyancy is the upward force a fluid exerts on an object placed in it. If that force is greater than the object's weight, it floats; if less, it sinks. It's why ships float and why you feel lighter in water.

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Key things to understand

  • 1It's the upward push a fluid gives an object.
  • 2Float if buoyant force > weight; sink if less.
  • 3It depends on how much fluid the object displaces.
  • 4It explains floating ships and lighter-feeling bodies in water.

Frequently asked questions

What is buoyancy?
The upward force a fluid exerts on an object, which determines whether it floats or sinks.
Why do heavy ships float?
Their shape displaces enough water that the upward buoyant force exceeds their weight.
What is Archimedes' principle?
An object is pushed up by a force equal to the weight of the fluid it displaces.

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