Buoyancy and Archimedes' Principle

The video explains why heavy objects seem lighter underwater due to buoyancy. It introduces Archimedes Principle, which states that the buoyant force on a submerged object is equal to the weight of the fluid displaced. The principle was discovered by Archimedes in the 3rd century BC. An example is given where a 25 kg weight displaces 20 kg of water, making its apparent weight 5 kg underwater. The video concludes by encouraging viewers to understand the principle when observing feats of strength underwater.

Why do heavy objects appear to weigh less when submerged in water?

• Because water is denser than air

• Due to the object's shape

• Because water reduces gravity

• Due to the buoyant force acting upwards

What happens to an object when it is submerged in a liquid?

• It becomes heavier

• It dissolves in the liquid

• It floats to the surface

• A buoyant force pushes it upward

Who discovered the principle that explains buoyancy?

• Isaac Newton

• Albert Einstein

• Archimedes of Syracuse

• Galileo Galilei

What does Archimedes' Principle state about the buoyant force?

• It is twice the weight of the object

• It is equal to the weight of the fluid displaced

• It is equal to the weight of the object

• It is half the weight of the fluid displaced

In the example given, what is the apparent weight of a 25 kg object that displaces 20 kg of water?

• 25 kg

• 20 kg

• 5 kg

• 0 kg

How does the buoyant force affect the apparent weight of an object underwater?

• It increases the apparent weight

• It decreases the apparent weight

• It doubles the apparent weight

• It has no effect on the apparent weight

What is the relationship between the weight of displaced fluid and the buoyant force?

• The buoyant force is equal to the weight of the displaced fluid

• The buoyant force is less than the weight of the displaced fluid

• The buoyant force is greater

• They are unrelated

What should you explain to a friend lifting weights underwater?

• The weight is heavier underwater

• The water makes the weight disappear

• Archimedes' Principle and buoyant properties

• The weight is unaffected by water