Need help with homework problem

AI Thread Summary
The discussion revolves around calculating the tension in a cord connecting two boxes, one on an inclined plane and the other on the floor. A force of 13 N is applied to a 1.2 kg box on a 38° incline, while a 5.0 kg box is on the floor. The equations used include m1a = T and m2a = F - T - m2gsin(theta), with an attempt showing T = 5.76 N. A user emphasizes the importance of a free body diagram for solving the problem, sharing a link to their diagram. The conversation highlights the necessity of visual aids in understanding physics problems.
phyzziksn00b
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Homework Statement


In Figure 5-65, a force of magnitude 13 N is applied to a FedEx box of mass m2 = 1.2 kg. The force is directed up a plane tilted by ? = 38°. The box is connected by a cord to a UPS box of mass m1 = 5.0 kg on the floor. The floor, plane, and pulley are frictionless, and the masses of the pulley and cord are negligible. What is the tension in the cord?

Homework Equations


m1a=T
m2a=F-T-m2gsin(theta)
(im not sure if these are right)

The Attempt at a Solution


T=F-m2gsin(theta)
T=(13)-(1.2)(9.8)(sin38)
T=5.75982105
 
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phyzziksn00b said:

Homework Statement


In Figure 5-65, a force of magnitude 13 N is applied to a FedEx box of mass m2 = 1.2 kg. The force is directed up a plane tilted by ? = 38°. The box is connected by a cord to a UPS box of mass m1 = 5.0 kg on the floor. The floor, plane, and pulley are frictionless, and the masses of the pulley and cord are negligible. What is the tension in the cord?

Homework Equations


m1a=T
m2a=F-T-m2gsin(theta)
(im not sure if these are right)

The Attempt at a Solution


T=F-m2gsin(theta)
T=(13)-(1.2)(9.8)(sin38)
T=5.75982105

Can you please draw the free body diagram and attach it? You cannot possibly do these problems without a free body diagram (Well, that's not true, but it's a stupid idea to do these without one)
 
<img src="http://img.photobucket.com/albums/v48/CianiMoni235/FBD.jpg">

i think this is right? sorry about the weird way i drew it
 
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ahh why doesn't it show up?
does it work if you just copy and paste the link into the browser?
 
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