Recent content by Miopen

I am trying to figure out if there is a way to measure muscle strain. If I apply a force F to compress a hand grip to the maximum distance x The work done to compress the hand grip is F*x Work done = Fx Since work done = energy used, I can change the equation to: Energy used = Fx When...

You are right. A classical question “why does holding something up cost energy while no work is being done?” If I insist on measuring the amount of energy used, not by work done on the object, not by thermodynamics, with addition of time factor, can this be done? I will change the question...

Now I get it. Let P be the constant of proportionality, then x = P/D Assuming x increases by 1mm while D decreases by 6m 0.001 = P / 6 P = 0.001 * 6 = 0.006 (m2) From equation (a), work done = ½ k x2 , substituting x for P/D work done = ½ k (P/D)2 - dimensionally Nm = Nm-1 (m4...

I am not good in physics and math but I will try. x is in mm, D is in meter. Depending on age, x can be stretched to around 1 mm, and D, the near point or amplitude of accommodation 10-15 cm. When x is zero (lens relaxed), D is infinity (or 6 m is as good as infinity when rays entering the eyes...

I have to read up on optics to understand your reply. It turns out that my question is not be related to optics. I will provide more information so that you understand how I come to the question. Elasticity is a physical property of material. The lens in our eye is elastic, and I only need to...

I am doing independent research to compute eye strain and I hit a problem. Hope someone can help. This is the situation. Work done to pull a spring is ½kx2. The human lens is like a spring. Linear, and obeys Hooke’s law. Work done to stretch the lens is also ½ kx2 (k=spring constant of...