A 1000kg boat is traveling at 90km/h when its engine is shut off. The magnitude of frictional force f(adsbygoogle = window.adsbygoogle || []).push({}); _{k}between boat and water is proportional to the speed v of the boar: f_{k}=70v, where v is in meters per second and f_{k}is in newtons. find the time required for the boat to slow to 45km/h.

The question does not ask for acceleration, so do I need to find the acceleration before finding the time?

In addition, Does any one knows how to use a math template for posting this type of question?

Thanks,

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# Homework Help: Friction question

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