From a physics perspective, energy would be integral of force * distance moved in direction of the force, so no motion should mean no energy used? So is it a biochemical effect of the way our muscles work? How exactly does that happen?
2006-10-24 12:25:24 · 5 answers · asked by Adrian W 1 in Science & Mathematics ➔ Medicine
Force is equal to mass times accelleration. This is the definition of force.
For an object to NOT accellerate in any one direction, it means that all forces acting on it are exactly balanced.
One way for this to happen is for there to be no forces acting on a body, relative to its environment.
On earth, the gravitational field of the planet earth itself imposes a force. This is represented by the "acceleration of gravity" or g = 9.8 m/s/s.
The amount of force applied to an object by the gravitational field of earth, is therefore proportional to the amount of mass of the object. This force is called the object's WEIGHT.
F (the weight of the object) = m( its mass) x g (the acceleration of gravity)
If the object is NOT moving, this is because the force being applied by gravity is equal to the opposing force being supplied by whatever is pushing opposite the direction of gravity. In your example, this would be the force being exerted by your arm.
If you apply an opposing force IN EXCESS of the force applied by the gravitational field, you will accelerate the object away from the earth. You will lift the weight. If you match the gravitational force exactly, you'll hold it steady. If you supply less than an opposing force, the gravitational force will accelerate the object earth-ward. The object will fall.
It's not complicated!
2006-10-24 16:48:16 · answer #1 · answered by bellydoc 4 · 0⤊ 0⤋
When you lift a stationary object up, you have added potential energy to the object - and the object, much like a coiled spring or a stretched rubber band will natually seek the position of least energy - and you are preventing it from doing this. The downward force exerted by the object must be met with an equal and opposite upward force - and that, my friend, is you.
2016-05-22 11:31:39 · answer #2 · answered by Anonymous · 0⤊ 0⤋
You are overcoming the intertial forces of the object in order to hold it up above the ground. You are also supporting the skeletal frame of your arm to hold the object. Your muscle is acting as a lever on the arm, so you are performing work by holding the object in stasis, overcoming the gravitational force acting upon it.
2006-10-24 14:38:39 · answer #3 · answered by phantomlimb7 6 · 0⤊ 0⤋
You are still fighting gravity, even if you are not moving the object.
2006-10-25 03:56:13 · answer #4 · answered by meltee 3 · 0⤊ 0⤋
technically you are not doing work, but you feel it due to muscles being flexed. gravity causes this.
2006-10-24 12:30:42 · answer #5 · answered by CzechMate 2 · 0⤊ 0⤋