How does your power output in climbing the stairs compare to the power output of a 100-watt light bulb? if your power could have been harnessed and the energy converted to electricity, how many 100-watt bulbs could you have kept burning during your climb?

-- My mass is roughly, let's say, 91.8 kilograms.

-- The 2nd floor of my house is, say, 5 meters high.

So, when I lift myself from the first to the 2nd floor, I do enough work to increase my gravitational potential energy by

PE = (mass) x (gravity) x (height)

PE = (91.8 kg) x (9.8 m/s²) x (5 m)

PE = 4,500 Joules

It takes me, say, 10 seconds to make the climb, so the power is

P = (work done) / (time to do the work)

P = (4,500 Joules) / (10 seconds)

P = 450 watts   (about 0.6 Horsepower)

This is enough power to keep four 100-W light bulbs and one 50-watter glowing at normal brightness.

But we have some work to do with the direction of the energy transfer.

When I stand at the bottom of the stairs and look up at the 2nd floor, I have a choice:  I can either climb the stairs to the 2nd floor, OR I can pedal my generator-bike and light some lightbulbs.  NOT BOTH.

I have energy in my blood and my muscles, which I can use to do work:  

-- If I use the energy to lift my mass to the 2nd floor, then the energy goes into the mass and becomes gravitational potential energy.

-- If I convert my muscle energy somehow to electrical energy and light some bulbs with it, then it goes to the bulbs and nowhere else.  I can't BOTH lift mass, give it potential energy, AND light bulbs.  

I can use my energy to climb stairs, OR chop wood, OR pump water, OR climb a ladder, OR turn an electrical generator, OR play with my dogs, OR run around the block, OR let my brain use the energy to solve some math problems.  Or I can distribute my energy, some here and some there, to do many things.

But I CAN'T use the SAME energy to do more than one thing.

the order for strong to weak forces such as

strong nuclear force → electromegnetic force → weak nuclear force → gravitational force

the fundamental forces are those forces that act between to objects or element to make interactions. there are four types of fundamental forces such as strong and weak nuclear forces (due to protons and electrons), electromagnetic force (due to the motion of electrons) and gravitational force (due to orbital movement of the planet). if these forces are arranged on the basis of their maximum strength then the order is

strong nuclear force → electromegnetic force → weak nuclear force → gravitational force

54 degrees incident angle = reflected angle

angle is from normal turned to line of ray