Today, we learned three new equations:
W = |F| |Δd| cos θ
W net = E kb - E ka = ΔE k
W net = F net (Δx) (cos θ)
W stands for work, which is measured in joule (J), and W net stands for net work or the sum of all the work being done on the system. When net work is positive, the system gains kinetic energy; when the net work is negative, the system loses kinetic energy. The first equation could be used to calculate horizontal energy that applied from an angle. The second and third equation helps us to find the net work in a energy system.
Something intrigued me is the question about is brain work count as useful work or wasting energy? Since in physics, more work have been done through thinking instead of expending energy to mechanically affect something. So does the thinking process expend energy? And where do all the energy go when we are thinking and studying?
