(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A train is travelling from left to right along a long straight horizontal track at 0.9km/min. A movie camera 1km away from the train is focused on the train.

a) How fast is the distance between the camera and the train changing when the train is 2km from the camera?

b) How fast is the camera rotating (in radians/min) at the moment when the train is 2km from the camera?

3. The attempt at a solution

I'm not sure how the equations should be written, most of the questions I've seen are lights on a pole (telling you its height and position) with an object moving toward or away from it, thus allowing trigonometric equations to be set up.

Part a) makes it sound like it's gonna be a linear equation with no trigonometry involved, but part b) confuses me with the camera's rate of rotation. Any help on how I should write the equations for these two parts is highly appreciated. Thanks in advance.

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# Homework Help: Application question

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