Final answer:
To calculate the upward force exerted by the liquid, we need to know the change in spring length caused by the object after being immersed in the liquid. The difference in forces before and after immersion, as determined by Hooke's Law, provides the buoyant force.
Step-by-step explanation:
The student is asking about the upward force exerted by a liquid on an object suspended from a spring. The change in spring length after the object is immersed in the liquid indicates the change in force due to buoyancy. This can be determined using Hooke's Law which states that the force exerted by a spring is directly proportional to its displacement from the equilibrium position, given as F = kx, where F is the force, k is the spring constant, and x is the displacement from the unstretched length.
To calculate the upward force exerted by the liquid, we would use the difference in spring length to determine the difference in the force before and after the object is immersed. Since we are not given the spring constant in the question, we must assume it remains consistent.
The spring stretched from 4.0 cm to 6.0 cm with the object hanging in air, which is a 2.0 cm stretch. The object is then immersed and the spring contracts to 5.0 cm, which is a 1.0 cm stretch. If we let Fair be the force due to the object in air, and Fliquid be the force while in the liquid, then the difference Fbuoyant = Fair - Fliquid gives the upward buoyant force exerted by the liquid.