Tagged Questions
0
votes
0answers
79 views
How can I measure the calories consumed in daily activity? [closed]
From a nice question here:
How are the calories in food calculated?
I can roughly understand how people provide the data of calories in certain food.
However, I am still confused about 2 things.
1) ...
1
vote
0answers
32 views
Is energy applied by the muscle when it holds a body in the air? [duplicate]
Possible Duplicate:
Why does holding something up cost energy while no work is being done?
We all know the following Newtonian formulas:
PotentialGravitationEnergy=m*g*h
Kinetic Energy = ...
21
votes
7answers
3k views
Why does holding something up cost energy while no work is being done?
I read the definition of work as
$$W ~=~ \vec{F} \cdot \vec{d}$$
$$\text{ Work = (Force) $\cdot$ (Distance)}.$$
If a book is there on the table, no work is done as no distance is covered. If I ...
