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Physics
Relative motion

In daily life we often come across movement called
mechanical motion. This is the change of position
of a moving object relative to other objects. Every
type of motion is relative depending on your
reference point, particularly whether the object
is stationary (at rest) or moving. This is called the
textbooks nis edu kz
system of reference. The total observed distance
covered by an object depends on its trajectory but
also the observer’s point of reference.

Imagine you are standing on a platform waiting for a
train, playing with a tennis ball. You are throwing the
ball up and catching it when it drops back down. You
then look up at a passing train and another person
inside the train is doing the same thing. But as you
are standing outside the train, it looks like the ball has
moved in a big curve. Motion and the trajectory are
dependent on the observer!

OVER TO YOU!

1. Draw a trajectory of the motion of the Earth relative to the Sun. Calculate the
distance covered by the Earth moving around the Sun.

2. Imagine you are a tourist sightseeing around Almaty. Your route starts from the
Kazakhstan Hotel, then you go 580 m up toward the National Museum, then you
go 600 m straight toward Republic Square and then you travel a further 970 m to
the Circus by bus. After the Circus, you travel 1.3 km to the cableway station by bus,
then 620 m up to the Medeo via cableway. Then you travel 39 m by bus to return to
your hotel. Compare the distance you have covered and your displacement.

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