Captain Zappo
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Torque on a "see-saw" type object
I had this question on my Physics test last week. I missed it, and it's now time to do test corrections. I have read through the section once again, but I keep on getting the same answer.
A uniform plank XY is supported by two equal 120-N forces at X and Y, as shown. the support at X is then moved to Z (half-way to the plank center). The supporting force at Y then becomes:
A. 40
B. 160
C. 60
D. 80
E. 240
I keep getting 60. I know that the net torque must remain 0, so as to keep the object from rotating. That being said, I cannot seem to come up with the correct answer (D).
Here's what my logic was:
If you move the point X, halfway to the center, it will produce 1/2 the amount of torque. So, the force at Y must decrease by 1/2 so as to keep the object in rotational equilibrium.
Please help me cite my error. Thank you in advance
I had this question on my Physics test last week. I missed it, and it's now time to do test corrections. I have read through the section once again, but I keep on getting the same answer.
A uniform plank XY is supported by two equal 120-N forces at X and Y, as shown. the support at X is then moved to Z (half-way to the plank center). The supporting force at Y then becomes:
A. 40
B. 160
C. 60
D. 80
E. 240
I keep getting 60. I know that the net torque must remain 0, so as to keep the object from rotating. That being said, I cannot seem to come up with the correct answer (D).
Here's what my logic was:
If you move the point X, halfway to the center, it will produce 1/2 the amount of torque. So, the force at Y must decrease by 1/2 so as to keep the object in rotational equilibrium.
Please help me cite my error. Thank you in advance