Question

Standing in water up to neck level reduce compression force of body weight by:

a) 25%
b) 50%
c) 75%
d) 100%

Answer 1

Standing in water up to one's neck significantly reduces the compression force of body weight due to the buoyant force, but it does not completely eliminate it, as 100% would suggest.

Step-by-step explanation:

When a person is standing in water up to their neck, the water provides an upward buoyant force that opposes the force of gravity. According to Archimedes' Principle, this buoyant force is equal to the weight of the water that is displaced by the person's submerged body. Since the human body is slightly less dense than water, when completely submerged, a person will displace a volume of water equal to their own weight, effectively reducing the body weight compression force by approximately 100%.

However, if only submerged up to the neck, some of the body is still exposed to air and not providing buoyancy, so the reduction would be somewhat less. Without more specific data, we can generally say the reduction in compression force due to body weight is significant, possibly between 50% to 100%, but selecting from the given choices, (d) 100% would not be accurate as it implies complete submersion and weightlessness which is not the case when submerged up to the neck.

Answer 2

Standing in water up to neck level reduces the compression force of body weight by approximately 75%, as the buoyant force supports most of the body's weight. Thus the correct option is c.

Step-by-step explanation:

When standing in water up to neck level, the buoyant force acting on the body is equal to the weight of the water displaced by the body. As a result, the effective weight experienced by the body is reduced. The buoyant force is equal to the weight of the water displaced, thus in neck-level water, approximately 75% of the body weight is supported, reducing the compression force on the body by 75%.

When immersed in water, the body experiences a buoyant force due to the displaced water. This force counteracts a significant portion of the body's weight, reducing the compression force felt on the body. In neck-level water, the buoyant force counteracts around 75% of the body's weight, resulting in a reduction of the compression force by the same percentage.

This principle illustrates the significant relief on joints and muscles experienced while submerged in water, offering relief from the usual pressure exerted by body weight on land. Therefore, standing in water up to neck level diminishes the compression force by approximately 75%, providing a considerable reduction in stress on the body.

Therefore, the correct option is c.