- #1
Moayad
- 9
- 0
Homework Statement
Three forces are applied to a bracket. The directions of the two
30-lb forces can vary, but the angle between these forces is always 50. Determine
the range of values of for which the magnitude of the resultant of
the forces applied to the bracket is less than 120 lb.
http://www.gefoon.net/upload/7/278933efb0.jpg
2. Relevant equation:
Fnet,x=o
Fnet,y=0
The Attempt at a Solution
i tried to get this problem solved by using different ways, but none of these have given me any answers.
@= the angle between 30-lb forces
i tried this one :
Fnet,x= 100 cos(30)-30 cos(@)-30cos(@+50)=0
Fnet,y=100sin(30)-30sin(@)-30sin(@+50)=0
but, this does not seem right for me because i am not going to have range of the angle and i did not use 120 ,and alos the TI-89 did not give me any thing.
however, i used another way,
120> -100 cos(150)+30cos(150)+30cos($)+30cos($+50)
i tried to solve by Ti-89 but also nothing happned.
$= the angle between the x-postive axis to the first 30-lb force.
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my problem is i do not know how to deel with (the which the magnitude of the resultant of
the forces applied to the bracket is less than 120 lb.) ...
can anyone helps me with ASAP