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Radians Clock question (1 Viewer)

Aysce

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Hey guys.

Q. Find correct to three decimal places, the angle in radians through which the second hand of a clock turns in 7 seconds.

What I've learnt so far is that to find the angle you have to find the ratio of the arc to the radii within a circle, although I am unsure about what the dimensions may be?
 

AAEldar

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Well, we know there are 60 seconds in a minute correct? So after 60 seconds it has gone completely around the circle once.

What we want is to find the ratio of the angle that is drawn out, in comparison to the total angle size of the clock. What's the angle size of a full circle? 360 degrees!

So we divide 360 by 60 seconds to find how big the angle is after 1 second. We get 6 degrees obviously!

Now after 7 seconds? Multiply 6 by 7 and we get 42 degrees, but we don't want degrees! To change degrees to radians:



 

Aysce

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Ohh i geddit, thank you :)

Nice explanation !
 

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