1. What are balanced & unbalanced Forces??

2. Buoyant Force
Why is lifting a heavy object in water easier than lifting the same object on land?
The reason is that water pushes upon objects, this upward force is called a “ buoyant force” .
So because it pushes upon objects, they seem to weigh less.
The buoyant force isn’t always equal to the weight of an object, it is equal to the weight of the
fluid that the object displaces or pushes aside.

3. Buoyant Force
Large objects have a greater buoyant force acting on them, since they displace more water than smaller objects.
Buoyant force acts on the opposite direction from weight. As a result it makes objects float.
If the buoyant force on an object is equal to or greater than the object’s weight, the object floats.
If the object’s weight is greater than
the buoyant force, the object sinks.

4. Buoyant Force
Ships are made of steel & are very heavy, yet they float??
Ships are large, but they aren’t solid; they are filled with air.
A ship’s overall weight is the weight of it’s steel walls plus the air inside the ship.
This total weight is less than the weight of the water that the ship displaces.
The buoyant force is greater than the ship’s weight so it floats.