English Deutsch Français Italiano Español Português 繁體中文 Bahasa Indonesia Tiếng Việt ภาษาไทย
All categories

what are two forces acting on my body and what is the equal and opposite force

2007-01-23 03:07:29 · 3 answers · asked by Anonymous in Science & Mathematics Physics

3 answers

Gravity is pulling down on you, while the floor or ground you're standing on is pushing up on you. The forces are balanced, hence you're not accelerating either up or down but staying put.

2007-01-23 03:16:42 · answer #1 · answered by . 4 · 0 0

There are but four fundamental forces in our known universe: gravity, electro magnetic (EM), and the weak and strong atomic forces. [See source.] The atomic forces do not exceed the size of atomic nucleii; so they do not affect you.

Gravity pervades everything; so, surely, you are being affected by it. In fact, your weight is really the force of gravity acting on your mass (m). Mass is a measure of inertia...the resistance to change in velocity. Weight can be described as W = mg; where g = 9.81 m/sec^2 or 32.2 ft/sec^2 which is acceleration due to the force of gravity at Earth's surface.

So gravity is pulling you towards the center of Earth; what's preventing you from sinking into the magma and molten iron at its center...EM forces. They are the opposite forces pushing back against your weight. Thus F = W or another way to put it F - W = 0, which means the EM force (F) exactly cancels out your weight (W) so you don't sink into the Earth you are standing on.

Where do the EM forces come from? They are from the electrons surrounding the atoms on the souls of your feet and in the ground/cement/asphalt/sand/stone/etc. you are standing on. The EM forces are repulsion forces because the electrons in the ground and in your feet are negatively charged. Like charges repel...it's that simple.

You may wonder how the electrons around atoms in and under your feet can cancel out the force of gravity. After all, gravity is everywhere, but the atoms are located just under and in your feet. Turns out gravity is a very weak force. In fact, despite it being everywhere, it is the weakest of the four forces. [See source.] As a consequence, relatively few atoms (although there are a lot in your feet) have enough EM force to cancel out the force of gravity pulling you downward.

There is one other set of forces not included in the four fundamental forces...virtual force. Centripetal and cetrifugal forces are in this set. They are not one of the four, but they result from the fact that mass has inertia, which means mass wants to stay put if it is at rest or stay going in a straight line at constant velocity if it is moving.

For example, when you spin a wheel with mass, the wheel's molecules spinning around the spin axis really want to fly out on a straight line rather than wrap around that axis. Thus, to keep those molecules in the spinning wheel from flying out and, thus, shattering the wheel, a force, called centripetal force, keeps pulling them back; so they continue to spin around the axis. Check this out:

"Objects moving in a straight line with constant speed have constant velocity and require no force to do so, since they experience no acceleration (see Inertia). However, an object moving in a circle at constant speed has a changing direction of motion. Since velocity is a vector with both speed and direction, a changing direction implies a changing velocity. The rate of this change in velocity is the centripetal acceleration." [See source.]

Thus, that "centripetal acceleration" acting on your body creates centripetal force; so if your massive body is sitting on a merry-go-round that is spnning, you have the virtual centripetal force acting on you in addition to gravity and EM. Centripetal force is counter acted by centrifugal force, which is the name given to the virtual force that wants you to fly off that horse and into the crowd. Thus, centrifugal force is pulling you off the merry-go-round, but centripetal force is pulling into its spin axis...the two forces offset each other.

2007-01-23 12:29:00 · answer #2 · answered by oldprof 7 · 0 0

god is one his opposite force is satan

another is gravity its opposite forse is the ground

2007-01-23 11:18:45 · answer #3 · answered by Anonymous · 0 1

fedest.com, questions and answers