general question about linear velocity

xdem713o

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In problems such as the hour/ minute hands of a clock... how can one find the linear velocity of a minute hand when your only given the length of that minute hand. Would you take half of the length that they give you.. which would make it the radius? I feel as though linear velocity is more complicated than angular velocity.
 
In problems such as the hour/ minute hands of a clock... how can one find the linear velocity of a minute hand when your only given the length of that minute hand. Would you take half of the length that they give you.. which would make it the radius?

No. The stated length of a minute hand will always be the radius.
 
So, how do you find the linear velocity from the length of the hand given?
 
how do you find the linear velocity from the length of the hand given?

For clocks, all the problem needs to state is the radius of the hand. You already know the angular velocity:

12 hours for one revolution of the hour hand
60 minutes for one revolution of the minute hand
 
xdem713o said:
In problems such as the hour/ minute hands of a clock... how can one find the linear velocity of a minute hand when your only given the length of that minute hand. Would you take half of the length that they give you.. which would make it the radius? I feel as though linear velocity is more complicated than angular velocity.

Would you take half of the length that they give you.. which would make it the radius? - No - the radius is the length of the hand (this is an assumption since the hand of a clock generally extend "a little bit" beyond the center of the clock. We assume that while giving the length of the minute hand they measured from the center to the tip)

So you know r = lenght of the minute hand

you know angular speed of the minute hand = 2?/hour = (?/30)/min = (?/1800)/sec

Now you can find the "magnitude" of the linear velocity (speed) of the "tip" of the minute hand = angular speed * radius

Remember that "...find the linear velocity of a minute hand when ..." does not make sense - because the linear speed will be different at different "spot" of the minute hand (the tip having the highest speed).
 
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