Answer:
To determine the force needed to support the 160-kg iron anchor submerged in seawater, we need to take into account the buoyant force acting on the anchor.
The buoyant force is the upward force exerted on the anchor due to the water it displaces, and it is equal to the weight of the water displaced by the anchor. The weight of the displaced water is equal to the volume of the anchor submerged in water multiplied by the density of seawater.
First, we need to calculate the volume of the anchor. We can assume that the anchor is a rectangular solid with dimensions 1 m x 1 m x 0.5 m. Therefore, the volume of the anchor is:
Volume of anchor = length x width x height = 1 m x 1 m x 0.5 m = 0.5 cubic meters
The density of seawater is approximately 1025 kg/m^3. Therefore, the weight of the water displaced by the anchor is:
Weight of water displaced = volume of anchor x density of seawater
= 0.5 cubic meters x 1025 kg/m^3
= 512.5 kg
According to Archimedes' principle, the buoyant force acting on the anchor is equal to the weight of the water displaced by the anchor, which is 512.5 kg. Therefore, the force needed to support the 160-kg iron anchor when it is submerged in seawater is:
Force = weight of the anchor - buoyant force
= 160 kg x 9.81 m/s^2 - 512.5 kg x 9.81 m/s^2
= 1173.6 N
Therefore, approximately 1173.6 newtons of force are needed to support the 160-kg iron anchor when it is submerged in seawater.