Final answer:
The assumption of the same specific force at two sections of a channel does not guarantee that the specific energies are equal or that the channel is horizontal. While an assumption of negligible or zero friction is inherent in Bernoulli's equation, the channel's inclination is unrelated to the specific force condition.
Step-by-step explanation:
The question relates to the concept of specific force in fluid mechanics, particularly within open channel flow. The specific force is defined at a section as the force exerted by the fluid weight and the dynamic pressure force on a horizontal bed per unit width of the channel. When the specific force at two sections of a channel is the same, it implies certain conditions about the flow and the geometry of the channel.
Option A suggests that the specific energies at the two sections are equal. However, having the same specific force does not necessarily mean that the specific energies are equal because the flow depth could be different at the two sections. Option B implies that the boundary friction is negligible or zero, which is a condition typically assumed in Bernoulli's equation application for an ideal fluid. Option C indicates that the channel is inclined, which is not directly related to the uniformity of specific force. Option D suggests that the channel is horizontal. This too is not necessarily implied by the uniform specific force, as an inclined channel could still meet this condition if the flow is steady and uniform.
To summarize, the assumption that the specific force at two sections is the same does not necessarily imply any of the options given completely, but option B regarding the boundary friction being negligible or zero is generally part of the assumptions used in the derivation of Bernoulli's equation, which relates to energy conservation in fluid flow.