A lemonade bottle immersed in the river weighs 1.5 N, and when put on the shore

A lemonade bottle immersed in the river weighs 1.5 N, and when put on the shore it weighs 6.5 N. Calculate the Archimedean force acting on the bottle.

The weight of a bottle of lemonade in water will be equal to the difference between two directly opposite forces: gravity and Archimedes’ buoyancy.
P = Ft – Fa, where P is the weight of a bottle of lemonade in water (P = 1.5 N), Ft is the weight of a bottle of lemonade on the shore (gravity acting on the bottle, Ft = 6.5 N), Fa is the force Archimedes (H).
Let’s express and calculate the force of Archimedes:
Fa = Ft – P = 6.5 – 1.5 = 5 N.
Answer: The force of Archimedes is 5 N.