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In this tutorial learn about position , distance and displacement
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in this video we will learn about
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position distance and displacement in
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our daily life we see lots of things
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moving around us for example car passing
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through from one place to another person
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riding on a bicycle and many other
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things in scientific term an object is
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said to be in motion if it changes its
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position with the passage of time and if
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it does not changes its position with
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the passage of time it is said to be at
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rest no both motion
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and rest are relative terms for example
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a mobile kept on a table is resting at
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its position but it is moving in the
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sense as earth is rotating on its axis
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so for a person seeing mobile from Earth
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it is at rest and for personal moon
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earth seems to change its position with
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time and so mobile is also moving now
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simplest case of motion is rectilinear
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motion
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which is the motion of an object along a
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straight line
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in our discussion of describing the
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motion of an object we will treat the
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object as a point object
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check now object under considerations
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can be treated as a point object if size
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of the object is much smaller than the
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distance traveled by eight in a
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reasonable time duration for example
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length of a motor car traveling a
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distance of 500 kilometer can be
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neglected with respect to the distance
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travelled by it here in kinematics we
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study is the ways to describe the motion
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without going into the cause of motion
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now first concept of kinematics we would
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like to discuss is position
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now to locate a position of a particle
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in motion or at rest we need a frame of
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reference now simplest way to choose a
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frame of reference is to choose three
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mutually perpendicular axis that can be
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labeled as x y&z axis so let me draw
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frame of reference
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so this is a frame of reference and we
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can level each of his three mutually
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perpendicular axes as x-axis y-axis and
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z-axis now such a system of labeling
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position of an object is known as the
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rectangular coordinate system
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let a be the position of any point in
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rectangular coordinate system and it can
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be labeled as a x y and z so this
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position is x here it is why
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and this is Z at this point o is the
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point of intersection of three mutually
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perpendicular axis and is known as
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region of frame of reference this point
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Oh to measure the time we can also
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attach a clock with this frame of
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reference if any one or all of the
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coordinates of the object under
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consideration changes with time in the
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frame of reference the the object is
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said to be in motion with respect to
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this frame of reference otherwise it is
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said to be at rest with respect to this
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frame of reference now for describing a
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motion of particle in one dimension
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we only need one off of the three
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coordinate axis that is
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that is we can either choose X Y or Z X
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is for the description of motion of the
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particle
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No
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motion of an object along spirit line
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a long straight line
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is an example of motion in one dimension
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one dimension motion a position of any
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object can be measured with respect to
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origin this as the line of motion of the
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particle this is the origin from where
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the particle starts this is suppose 100
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kilometers 200 kilometers 300 kilometers
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and so on this is positive x-axis and
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here on the left hand side gate div
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x-axis see this is minus hundred minus
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200-300 and so on no
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suppose a man walks along positive
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x-axis at time T the man is at a
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distance hundred kilometer fall from the
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region at t1 it is at 200 kilometers and
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so on so we can measure position
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awful man walking
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along positive x-axis with the passage
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of time
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naw positions on the right hand side of
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the region has positive values and on
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that of the left hand side of the origin
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has negative values now after describing
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the position of an object we will not
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define the distance and displacement
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no I will first draw my figure or to
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describe the distance and displacement
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of an object
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now this graph shows an object is is
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that position p at time t1 and it would
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position are at time t2 in the time
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interval from t1 to t2 particle has
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traveled path P Q R and length of the
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path P Q R is the distance travelled by
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the object in the time interval t1 to t2
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now we connect the initial position of
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the object beam with its final position
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are through a straight line so let me
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draw connect the line now i have
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connected this loud this point p and r
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through a state line and this straight
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line is the displacement
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of the object so this placement of the
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object has both magnitude
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and direction
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so since the displacement of the object
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has both magnitude and direction it is a
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vector quantity
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now magnitude of a displacement vector
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is equal to the length of straight line
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joining initial and final position and
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its direction points from the initial
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position of the object towards the final
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position of the object in contrast to
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displacement distance is a scalar
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quantity
#Primary & Secondary Schooling (K-12)
#Physics