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John Mcrain
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How do I know is this object at rest,moving to the left or moving to the right ?
If it were moving to the left then is not at rest,if it were moving right than is not at rest...Dale said:If it were moving left is it at rest? If it were moving right is it at rest? What do you conclude?
My friend look at this object and say: this object can only stay at same position,he said imagine two mens pulls same object with rope with same force in opposite direction,so object must be at rest.Ibix said:I think your word order was not quite correct and your question may have been misunderstood. I think the question is, "how can I tell if this object is at rest, moving to the left, or moving to the right".
If you are on a train, what clues are there that you are moving?
How the object is moving depends on the reference frame you use.John Mcrain said:How do I know is this object at rest,moving to the left or moving to the right ?
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I draw refernece frame origin in my pictureA.T. said:How the object is moving depends on the reference frame you use.
Are you asking about the rest frame of the object, before any forces were applied?John Mcrain said:My friend look at this object and say: this object can only stay at same position,he said imagine two mens pulls same object with rope with same force in opposite direction,so object must be at rest.
No.John Mcrain said:Is now clear where confusion comes?
My friend look at this object and say: this object can only stay at same position,he said imagine two mens pulls same object with rope with same force in opposite direction,so object must be at rest.A.T. said:Are you asking about the rest frame of the object, before any forces were applied?No.
You didn't answer my question: Are you asking about the rest frame of the object, before any forces were applied?John Mcrain said:My friend look at this object and say: this object can only stay at same position,he said imagine two mens pulls same object with rope with same force in opposite direction,so object must be at rest.
Depends on the reference frame.John Mcrain said:But if this object is plane ,and red force is drag and blue is thrust ,than object moving to the right..
Just use Newtons 2nd Law. And stop asking about movement without specifying the reference frame. It's a meaningless question.John Mcrain said:So it seems we don't know from forces vector,what happening with this object..
A.T. said:You didn't answer my question: Are you asking about the rest frame of the object, before any forces were applied?
Imagine human eyese is at origin of frame and looking at this object..A.T. said:You didn't answer my question: Are you asking about the rest frame of the object, before any forces were applied? Depends on the reference frame.Just use Newtons 2nd Law. And stop asking about movement without specifying the reference frame. It's a meaningless question.
Oops, then I misunderstood the question. My apologies @John McrainIbix said:I think your word order was not quite correct and your question may have been misunderstood. I think the question is, "how can I tell if this object is at rest, moving to the left, or moving to the right".
If you are on a train, what clues are there that you are moving?
That is correct. From the forces you only know the acceleration. You cannot determine the velocity from the forces alone. In fact, the object could even be moving up or down.John Mcrain said:So it seems we don't know from forces vector,what happening with this object..
Is now clear where confusion comes?
No.Ibix said:I think your word order was not quite correct and your question may have been misunderstood. I think the question is, "how can I tell if this object is at rest, moving to the left, or moving to the right".
If you are on a train, what clues are there that you are moving?
How is possible to object moves up and down if forces act only left and right?Dale said:That is correct. From the forces you only know the acceleration. You cannot determine the velocity from the forces alone. In fact, the object could even be moving up or down.
In order to determine the motion completely in addition to the forces you must also specify the initial conditions: the initial position and the initial velocity.
If this object is in a car with you and you are driving on the highway at 50 miles/hour, you will say that the object is not moving.John Mcrain said:How do I know is this object at rest,moving to the left or moving to the right ?
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If its initial velocity were up then it would continue to move up at the same speed even with forces only left and right.John Mcrain said:How is possible to object moves up and down if forces act only left and right?
Then it starts at rest and remains at rest. It does not move. Is that clear why? There is no net force to cause it to accelerate. Since it doesn't accelerate its velocity doesn't change. Since its velocity starts at zero and doesn't change then it stays at zero. Since its velocity is zero it is at rest.John Mcrain said:Initial positon is at this place like its drawn at picture and initial velocity is zero in realtion to origin at picture..
Ok thanks for answer,so answer on my qestion lie in inital conditions.Dale said:If its initial velocity were up then it would continue to move up at the same speed even with forces only left and right.
Then it starts at rest and remains at rest. It does not move. Is that clear why? There is no net force to cause it to accelerate. Since it doesn't accelerate its velocity doesn't change. Since its velocity starts at zero and doesn't change then it stays at zero. Since its velocity is zero it is at rest.
Forces produce acceleration, not velocity. That was Newton's key insight over Aristotle.
Yes! ExactlyJohn Mcrain said:Ok thanks for answer,so answer on my qestion lie in inital conditions.
So if inital conditions was moving to the right at 100km/h,then object is still moving to the right at 100km/h?
Then in that frame it will remain zero.John Mcrain said:... initial velocity is zero in relation to origin ...
Couldn't they produce the same results by doing this on a moving train?John Mcrain said:My friend look at this object and say: this object can only stay at same position,he said imagine two mens pulls same object with rope with same force in opposite direction,so object must be at rest.
It's not marked on the diagram so you don't know.John Mcrain said:How do I know is this object at rest,moving to the left or moving to the right ?
I was wondering why it took so long for someone to quote Sir Isaac.russ_watters said:This is Newton's first law.
To determine the direction an object is moving, you can use the concept of vectors. A vector is a quantity that has both magnitude (size) and direction. By measuring the displacement of the object over a period of time, you can calculate the velocity vector and determine the direction of motion.
Yes, you can use the position of an object to determine its direction of motion. By comparing the position of the object at different points in time, you can calculate the displacement and determine the direction of motion. However, this method may not be as accurate as using the velocity vector.
The direction of motion is a crucial component of an object's velocity. Velocity is a vector quantity, meaning it has both magnitude and direction. Therefore, even if an object is moving at the same speed, a change in direction will result in a change in velocity.
Yes, an object can change direction without changing its velocity. This is known as uniform circular motion, where the object moves in a circular path at a constant speed. In this case, the velocity vector is constantly changing, but the magnitude of the velocity remains constant.
You can determine the direction of motion without knowing the object's speed by using the concept of relative motion. If you observe the object from a different reference frame, you can compare its position at different points in time and determine the direction of motion. However, to calculate the speed, you will need to know the distance and time taken by the object to travel that distance.