Newton's Third Law and Inertia
Newton's Third Law and Inertia
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NEWTON'S THIRD LAW states that when TWO objects interact, the forces they exert on each other are EQUAL and OPPOSITE.
In other words, if OBJECT A exerts a force on OBJECT B, OBJECT B will exert an EQUAL and OPPOSITE force back onto OBJECT A.
If you stand and PUSH against a wall with your hands, you are exerting a force on the wall (the action force). According to Newton's Third Law, the wall PUSHES BACK against your hands with an EQUAL and OPPOSITE force (the reaction force). Even though it might not be obvious, because the wall is sturdy and doesn't move, the forces are still present and EQUAL in magnitude.
In this situation, you DON'T move, nor does the wall, but the force pairs are there, EQUAL in size and OPPOSITE in direction. The reason you and the wall don't move (assuming it's a solid wall) is because the wall is strong enough to withstand your push without breaking or moving, and your muscles are reacting to the resistance provided by the wall, allowing you to maintain your balance and not fall backward.
This interaction causes the pin to be knocked over (if the force is sufficient) while the bowling ball experiences a small change in velocity due to the force exerted by the pin. The effect on the bowling ball is less noticeable due to its much greater mass compared to the pin.
INERTIA is an object's natural tendency to keep doing what it's currently doing — to stay still if at rest, or keep moving if in motion, unless an external force acts on it.
It is not just a measure of how much something weighs (that's mass), but how much it resists speeding up or slowing down.
INERTIAL MASS is a measure of how difficult it is to CHANGE the VELOCITY of an object. It tells us how much force would be required to give an object a certain acceleration. It's the ratio of FORCE OVER ACCELERATION.
A larger inertial mass means an object will NOT speed up or slow down as easily — it will RESIST changes in motion more than an object with a smaller inertial mass.
This is why a bowling ball is harder to start rolling, or stop, compared to a basketball.
NEWTON'S THIRD LAW states that when TWO objects interact, the forces they exert on each other are EQUAL and OPPOSITE.
In other words, if OBJECT A exerts a force on OBJECT B, OBJECT B will exert an EQUAL and OPPOSITE force back onto OBJECT A.
If you stand and PUSH against a wall with your hands, you are exerting a force on the wall (the action force). According to Newton's Third Law, the wall PUSHES BACK against your hands with an EQUAL and OPPOSITE force (the reaction force). Even though it might not be obvious, because the wall is sturdy and doesn't move, the forces are still present and EQUAL in magnitude.
In this situation, you DON'T move, nor does the wall, but the force pairs are there, EQUAL in size and OPPOSITE in direction. The reason you and the wall don't move (assuming it's a solid wall) is because the wall is strong enough to withstand your push without breaking or moving, and your muscles are reacting to the resistance provided by the wall, allowing you to maintain your balance and not fall backward.
This interaction causes the pin to be knocked over (if the force is sufficient) while the bowling ball experiences a small change in velocity due to the force exerted by the pin. The effect on the bowling ball is less noticeable due to its much greater mass compared to the pin.
INERTIA is an object's natural tendency to keep doing what it's currently doing — to stay still if at rest, or keep moving if in motion, unless an external force acts on it.
It is not just a measure of how much something weighs (that's mass), but how much it resists speeding up or slowing down.
INERTIAL MASS is a measure of how difficult it is to CHANGE the VELOCITY of an object. It tells us how much force would be required to give an object a certain acceleration. It's the ratio of FORCE OVER ACCELERATION.
A larger inertial mass means an object will NOT speed up or slow down as easily — it will RESIST changes in motion more than an object with a smaller inertial mass.
This is why a bowling ball is harder to start rolling, or stop, compared to a basketball.
