ios - iPhone Accelerometer Values -

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my question iphone accelerometer. accelerometer measure acceleration or movement of iphone? mean if hold iphone , go 0mph 60mph, expect measure of acceleration increase in value 0 60, once reach 60, expect value return 0 since "no longer accelerating" moving @ constant speed. if accelerometer measure motion, expect register 0 60 , continue provide change in value move forward @ 60mph. sorry, looked @ few books, programmed code (values seemed small give recognizable result on short distances or speeds), , lot of web searches, , trying answer question.

thanx!

a couple of points:

  • the accelerometer never reads 0 because gravity , acceleration (and thing too). if ever reads 0 in deep doo-doo - have been cast adrift in space, or else in free-fall plunging towards ground.

  • when go 0 60, acceleration not "register 0 60". isn't acceleration is. isn't speed; it's rate of change in speed. lamborghini or vw bug? both go 0 60 acceleration might very, different.

    you might need read little physics textbook here, make simple, think of how hard being pressed against car seat! if not being pressed back, thrown side side, etc., horizontal acceleration 0 going 100 miles per hour.


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