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What's more accurate - a speedo or a satnav?
The speed recorded on my satnav is 3mph slower than the speedometer reading, which is likely to be accurate?
Asked on 19 March 2018 by Stephen BASFORD
Answered by
Honest John
The satnav shows your GPS speed across the surface of the planet triangulated by at least three satellites. So if you are on a flat, straight road, the speed it shows will be your true speed. Your speedometer will be out.
Tags:
speedometer
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