So as you already know, they may have some technical meanings. Force is sometimes measure in kg⋅m⋅s−2, or the Newton. One might express this more fundamentally as mass times acceleration. It can have a more mundane meaning in common speach, e.g., "a tour de force", "by force", etc. "Our forces were strong enough to defeat the Martian army." Power is a unit of energy transferred per time, e.g., kg⋅m2⋅s−3 or the Watt. It is the amount of work that is performed in a unit of time, and utilities companies provide it. Also, it has a common meaning. "My power to persuade isn't always effective." Strength can also have a meaning in material science, measure as toughness (a very involved and complicated topic). Suffice it to say that it also has a common meaning. "My strengths are in mathematics."

In physics, they have technical meanings. In ordinary usage, they are almost synonyms, and any differences are subtle shades of meaning. You can say "He is a powerful man," "he is a forceful man," "he is a strong man" and they all mean roughly the same thing. "Power" is connected to the idea of ability. "He has a lot of power in this town; he can get things done." "Force" is connected to the idea of being able to overcome something or somebody else, and to do something they are trying to stop you from doing. "He tried to hold the door closed, but she pushed hard and forced her way in." "Strength" can mean force or power, but it also can have a meaning that the other words don't have. "Strength" can mean the ability to resist force, the ability to remain unmoved. Thus, one could say "Steel beams have great strength," but you would not say "Steel beams have great power" or "Steel beams have great force."

Obviously you are using these words relative to each other. Power, Force, and Strength. Looking at the definitions of these words, power correlates to the application of strength and force (combined), similar to pressure. Strength is the ability to withstand pressure without the exertion of force( the state of being strong). Force is an energy, an attribute of movement. Basically when you add force to strength it becomes power. Just an Idea.

I believe that power is related to machines, force is related to "groups" and strength is related to humans abilities.