Why don't action-reaction forces cancel each other ?
79420
Hey babygurlgonnaloveonu you have asked what is totally QUESTION NUMBER ONE in physics. It's an exciting question which many teachers secretly don't understand and so their students get this hazy idea and kind of go thru the motions. \n\nWow, it is so basic, that it took a super-genius, I mean way smarter than Einstein, to figure it out. A good old farm boy, astrologer, magician & alchemist, religious fanatic, mathematician and all around kook. Yep. Sir Isaac Newton. You gotta wonder what kind of parents would name their kid "Sir"\n\nWell we all know what a force is, it is a sort of push or pull -- think of it as something that changes or *tries to change* the motion of stuff.\n\nNewton first figured out that if you leave a thing alone, or if the pushes and pulls on it cancel out, then it will sit there like a lump. Like those drivers wearing hats, and like sit there after the light has already turned green two minutes ago. \n\nOr else a thing  will keep moving in the same straight line direction and speed  like those drivers wearing hats who go 40 mph on the expressway with their turn signal blinking on and on. This is known as "THE HAT LAW".\n\nAll was well until he noticed that things move faster in an amount equal to how much you bully them or push them around. Twice the force, twice the fasterness and fasterness (also known as acceleration). This is called the "YOU BIG BULLY LAW".\n\nThen he discovered a fly in the ointment. His HAT and BULLY laws didn't really explain all that much. Something was gumming up this beautiful theory. We call it MASS and it is still an unknown mystery as to what it really is. So we vaguely call it the amount of stuff or matter in a thing. \n\nSo he found out that for a certain force the faster-isity (acceleration) is cut in half if you double the mass. The bully has to push twice as hard to fasterize two little kids. So he was like "I'll just add that in, and all will be cool". The "YOU BIG BULLY LAW" and "THE HAT LAW" totally did it all. Wa ta da babee!\n\nBut then Newton had a road accident. He was gunning his Harley over London bridge at like 250 when a bug  hit him in the mouth and knocked out one of his wooden teeth. He was all "Why am I so in pain?". And the bug as it squooshed said "Help! I'm a bug!"\n\nSo spitting out the splinters of his wooden tooth and the splattered bug, he had this revelation. He realized that because he was moving so fast, and the  bug slowed down so fast, that even a eentsy mass like a bug was like taking a hammer to his tooth. \n\nHe noticed that the force was equal to the mass of the bug times the speed of impact all happening in a brief moment. Since Newton spoke Latin (he  was the love child of Joe Newton and an Italian governess) he wrote "Fastus buggus ina momentum hurtus like crazy." Today we call this "momentum". It is just "mass times speed" or "force times a small moment of time". \n\nAnd he realized that the bug smashed up his tooth, but also that the bug was squashed (like a bug) because they were trading the EXACT same amount of momentum. The force on the tooth by the bug in the moment of time was PRECISELY equal to the  smacko-ing the tooth used to stop the bug dead. \n\nHe said "Hey, like he broke my tooth, but I killed him soooo dead!" He did the math and found that the force of the bug on the tooth was equal to the force of the tooth on the bug! \n\nNo way did the two equal forces cancel, after all, his tooth was hammered to splinters, and the bug was flattened. They were equal and opposite, but since one was on the tooth, and the other force was on the bug they did serious damage! Today we call this the "HELP I'M A BUG" law.\n\nNow our man 'Zack was all set. He wrote down his three laws:\n\nTHE HAT LAW (beeep! beeep! Move it Hat Guy!)\nTHE YOU BIG BULLY LAW (betcha can't kno
145884
Newtons 3rd Law,\nFor every action, there is an equal and opposite reaction.\n\nSo all of the instances given, there is both an action and reaction force occuring.
282006
Answer is 'acts in the direction opposite of motion."\n\nFriction always opposes motion. Therefore first one is wrong.\nFriction is equal to mu times the weight. and mu is not equal to one.Therefore second  one is wrong.\n Sliding friction is less than static friction\nTherefore Third   one is wrong.
685243
Either the object is not immovable or the force is not irresistible.  Both things can not be true at the same time.
591510
When you move your hand up, your flesh rises and the air that existed above it has been displaced.  There is a void -some free space where you hand was and the displaced particles rush to fill it.  \n\nIt says for every action there is an equal and opposite reaction - it does not say that the object being moved had both reactions.
771568
Basically you have the right idea. Use momentum (mass x velocity) for the motion and the sudden change in speed and/or direction (acceleration) and you get force x time = kinetic energy trying to rip you apart or squash you like a bug.
1081915
None of the above.\n\nIt will repel another positive change,\nattract a negative charge,\nand not interact with a neutral charge.
81552
If you disregard air resistance, both land at the same time.\n\nThe Earth's gravitational pull affects everything equally.
784797
Suppose there is load and two men are pulling it in one direction each one giving a force of 5N.\n\nIn the language of vector, two vectors of magnitude 5 are acting in the same direction,\n\nThe resultant is a vector of magnitude 10N in the same direction. \n\nIf they are pulling it in opposite direction the load will not move.\n\nIn this case the two vectors of equal magnitude are acting in opposite direction.\n\nThe resultant of these two vectors is zero.
35079
Newton's third law of motion - every action has an equal and opposite reaction. So the bullet firing out the front of the gun makes the gun go backwards an equal and opposite amount. Since the bullet weighs less than the gun, the gun does not kick back as fast as the bullet, but it does with the same force. This is why with powerful rifles and shotguns, you are supposed to keep the butt of the gun tight against your shoulder - so the kickback is transmitted smoothly into your body, instead of slamming into your shoulder and causing bruising.
39571
As you know, Newton's Third Law of Motion states that for every action there is always an equal and opposite reaction. This is applicable only to an action originating from a mass. When you consider a rocket, gas is ejected out from the thrust nozzle with great acceleration. This is achieved when a force is applied on the gas.\nNow, when a force is applied on the gas by the rocket to thrust it out, the gas exerts an equal and opposite force on the rocket, thereby resulting in acceleration of the rocket in the direction of the net resultant force. Thus there is no need for any atmosphere or body which exerts a reaction force other than the gas ejected!! So there you are !!!
819927
All objects react as if there were only a single force acting upon them. Let's say an object on your desk had a force of ten newtons pushing it to the east. Let's call that force positive 10 newtons. According to Newton's second law, it would accelerate (pick up speed) moving in an eastward direction. It had a single force acting upon it and since there was no opposing force we say that it was an unbalanced force. Now say the same object had another force of 10 newtons acting on it in a westward direction. Lets call that force negative 10 newtons. Now we have two forces and since they are equal but have opposite signs the algebraic sum is zero ([+10N] + [-10N] = 0). We now have balanced forces - equal but opposite. Remember I said that all objects react as if there were only one force acting upon them? Even though there are two forces acting in opposite directions on the object on your desk, that object reacts as if there were only one force acting upon it - a force of zero newtons. BTW, that sum force is called the resultant. So according to Newton's first law since a zero force is applied to the object it will remain at rest. In short, unbalanced forces result in movement, balanced forces don't.
765174
One force acts on one body the second acts on the other body.  It is easy to visualize if you are on a boat and push away from the deck.  You move by pushing on the deck.  You push to hard you can break something on the deck (and you still move if you didn't fall from the boat).
1065659
It is not possible unless there is some external force to initiate or continue the movement. The initial movement will get off set and reduced  in course of time.
6951
yes there is a reaction. If you are standing completely still and you are pushed the reaction is you move relative to the force applied and the resistance force of friction and inertia which varies depending on your mass.
556094
Friction is not a force... It just is... It only exists when two objects, or things are in contact with each other.\nIf a force is acting on an object to move it, friction acts in the opposite direction.. It's simple as that. Obviously if the force is not greater than the friction, the object will not move.\nSo the direction of friction is opposite to the direction of the bicycle's movement, so in the same "Direction" for both wheels.
838647
It's called "quantum entanglement" in which the quantum states of particles generated from an event are always "connected".  If a reaction produces a particle pair of opposite spins, those particles will always have opposite spins no matter where they are located.  So if you "flip" one, the other must flip instantly.