An object that floats in water weighs 20 N in air. a. What is the weight of the object in water?
b. What is the Upthrust acting on the object in water?
c. What is the weight of the water displaced by the object?

a. Weight of Object in Water = 20 N

b. Up thrust = 20 N

c. Weight of Water Displaced = 20 N

Explanation:

a.

The weight of the object remains same in the water as well. Because, the same force of gravity is acting there as well. Hence,

Weight of Object in Water = 20 N

b.

Since, the object floats on the water. Therefore, according to Archimedes' principle the up thrust force acting on the object must be equal to the weight of object:

Up thrust = Weight of object

Up thrust = 20 N

c.

From Archimedes' Principle, we know that the up thrust or the Buoyant force is equal to the weight of the water displaced by the object. therefore:

Weight of Water Displaced = Up thrust

Weight of Water Displaced = 20 N