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r-soy
Oct18-10, 11:08 AM
A typical compound archery bow requiers a force of 133 N to hold an arrow at "full drwa " ( pulled back 71 cm ). ssunimg that the bow obeys hooke's law . what is its spring constant ?



did conver 71 to m

did use k = W/x to find spring constant ?



plese help me ?

r-soy
Oct21-10, 06:07 AM
Hi

F =W/x= 133N/.71 m= 1.87N/m.



??

phyzguy
Oct21-10, 06:56 AM
This is kind of a stupid problem. A compound bow is specifically constructed so that its "spring constant" is not constant. If you've ever pulled one, you know that it takes much less force to hold it at full draw than it does to get it there. For a spring, F=-kx tells you that the force increases steadily as you increase the displacement, whereas for a compound bow F increases, then decreases again until you get to full draw.

Borek
Oct21-10, 07:33 AM
133N/.71 m= 1.87N/m

Replace batteries in your calculator.

r-soy
Oct21-10, 01:43 PM
hhhhhhhhhhhh

loooooooool
sorry the answer is 187.3