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If you are sitting still in your seat on a bus that is traveling 100 km/h on a highway, is your body at rest or in motion? Explain

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AL2006

The answer to the question is: YES.

Remember that every description of motion depends on the observer's 'reference frame'. In other words, motion is always RELATIVE TO something. There's no such thing as 'real' motion that is the same to everybody who measures it.

-- In the reference frame of somebody parked in the rest area, (or a chicken waiting to cross the road), you are moving to the East at 100 km/hr.

-- In the reference frame of the other passengers on your bus, you are at rest.

-- In the reference frame of a car driving at 120 km/hr in the same direction as your bus, you are moving WEST (backwards) at 20 km/hr.

-- In the reference frame of a bird flying North at 100 km/hr, you are moving South-East at 141 km/hr.

These measurements are all true and correct in THEIR reference frame. The measurement depends on the observer's motion just as much as it depends on YOURS.

That's why, when you asked "Is my motion ..." this or is it that, I had to answer YES. It could be either one. It depends on who's doing the measuring.