- #1
jwj11
- 37
- 0
[SOLVED] Two Situations of Tension... Same Thing?
A box is hanging with two wires. (Refer to diagrams). Find the two tensions.
My first question is, if the two diagrams are different situations that will lead to different answers? Personally I don't think they would... since the x coordinates still have to equal zero, with the same angles... but I'm not exactly sure, can someone please clarify the concept behind this?
Diagram 1
http://img252.imageshack.us/img252/329/yole7.jpg
Diagram 2
http://img339.imageshack.us/img339/5839/yo1yw5.jpg
T1*sin56 + T2*sin45 - 35N = 0
-(T1*cos56) + T2*cos45 = 0
Prepared for substitution
T2 = T1(cos56)/cos45
T1(sin56) + T1(sin45)(cos56)/(cos45) - 35N = 0
T1(sin56 + sin45*cos56/cos45) = 35N
Solved for T1 = 25N.
Plugged in and got T2 = 20N.
So based on those equations I get T1 = 25N, and T2 = 20N... but the answer key shows a way different answer so I am confused. Could it be that the answer key is wrong? Or maybe it is because of the two different situations I've shown above? I'm use to doing problems like diagram 2, but for this question it is shown like diagram 1?
Please let me know if I made a mistake, this is driving me crazy.
Homework Statement
A box is hanging with two wires. (Refer to diagrams). Find the two tensions.
My first question is, if the two diagrams are different situations that will lead to different answers? Personally I don't think they would... since the x coordinates still have to equal zero, with the same angles... but I'm not exactly sure, can someone please clarify the concept behind this?
Diagram 1
http://img252.imageshack.us/img252/329/yole7.jpg
Diagram 2
http://img339.imageshack.us/img339/5839/yo1yw5.jpg
Homework Equations
T1*sin56 + T2*sin45 - 35N = 0
-(T1*cos56) + T2*cos45 = 0
The Attempt at a Solution
Prepared for substitution
T2 = T1(cos56)/cos45
T1(sin56) + T1(sin45)(cos56)/(cos45) - 35N = 0
T1(sin56 + sin45*cos56/cos45) = 35N
Solved for T1 = 25N.
Plugged in and got T2 = 20N.
So based on those equations I get T1 = 25N, and T2 = 20N... but the answer key shows a way different answer so I am confused. Could it be that the answer key is wrong? Or maybe it is because of the two different situations I've shown above? I'm use to doing problems like diagram 2, but for this question it is shown like diagram 1?
Please let me know if I made a mistake, this is driving me crazy.
Last edited by a moderator: