Flagpole Stability: Calculating Maximum Tension

AI Thread Summary
The discussion focuses on calculating the maximum tension in a flagpole setup involving a horizontal pole and a stuntwoman. For part a, the minimum height for the guy wire attachment to ensure tension does not exceed 1070 N is determined to be 4.30 m. In part b, the challenge is to find the increase in tension if the wire is fastened 0.520 m below this height. The correct approach involves recalculating the angle using the new height and applying torque equations to find the resulting tension. The conversation emphasizes the importance of accurately applying trigonometric functions and torque principles in solving these physics problems.
MAPgirl23
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A uniform, horizontal flagpole of length 5.00 m and with a weight of 195 N
is hinged to a vertical wall at one end. A stuntwoman weighing 600 N hangs
from its other end. The flagpole is supported by a guy wire running from
its outer end to a point on the wall directly above the pole.

a) If the tension in this wire is not to exceed a force of 1070 N, what is
the minimum height above the pole at which it may be fastened to the wall?

b) If the flagpole remains horizontal, by how many Newtons would the
tension be increased if the wire were fastened a distance 0.520 m below
this point?

For a) I got 4.30m by tan(theta) = d/5m solve for theta then for d

How do I solve for b)?
 
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I used theta = arctan(d/x) = arctan(4.3/.52m) = 83.1 but it gives me a rounding off error
 
MAPgirl23 said:
For a) I got 4.30m by tan(theta) = d/5m solve for theta then for d

I used theta = arctan(d/x) = arctan(4.3/.52m) = 83.1 but it gives me a rounding off error
Your new angle is the solution to

tan(theta) = (d-.52m)/5m

where d is the 4,30m from the first part. With your new angle, you can still equate the magnitude of the torque of the wire to the magnitude of the torque of the pole plus the woman.
 
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