- #1
DB
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a small spider weighing about 6.0e-3 N, hangs on its thread from the branch of a tree. A horizontal wind blows the spider and the thread to and angle of 35 degrees from the vertical.
a)find the horizontal force of the wind on the spider
b)find the tension in the thread
i got a, here's wat i did..
i drew a free body diagram
first i made the x-axis the tensile force in the thread, so in that case, the horizontal force was -35 degrees from the x-axis and the gravitational force was -35 degrees from the y axis. knowing that the spider is in dynamic equilibrium, i resolved the components of F_h and F_g
so i knew that to solve for F_h i had to get at least 1 of the x',y' components of F_h and use trig to solve for the hypotneuse, i knew this because the net force on the spider has to be 0.
so:
[tex]0.006sin(35)=\sim 0.00344[/tex]
that gave me the x' component of F_h, so then the hypotneuse is
[tex]\frac{0.00344}{sin35}=\sim 0.0042[/tex]
so the force of the wind on the spider would have to be about 0.0042 N, which the answer book says is right.
b) here i don't know wat to do, i know wat tension is, but my teacher hasnt showed me how to do this, and its not in the book. i thought that the sum of F_h and F_g would give me F_t but that's not it, the answer 7.3e-3 N and i don't know how to get there, some help would be apreciated :)
a)find the horizontal force of the wind on the spider
b)find the tension in the thread
i got a, here's wat i did..
i drew a free body diagram
first i made the x-axis the tensile force in the thread, so in that case, the horizontal force was -35 degrees from the x-axis and the gravitational force was -35 degrees from the y axis. knowing that the spider is in dynamic equilibrium, i resolved the components of F_h and F_g
so i knew that to solve for F_h i had to get at least 1 of the x',y' components of F_h and use trig to solve for the hypotneuse, i knew this because the net force on the spider has to be 0.
so:
[tex]0.006sin(35)=\sim 0.00344[/tex]
that gave me the x' component of F_h, so then the hypotneuse is
[tex]\frac{0.00344}{sin35}=\sim 0.0042[/tex]
so the force of the wind on the spider would have to be about 0.0042 N, which the answer book says is right.
b) here i don't know wat to do, i know wat tension is, but my teacher hasnt showed me how to do this, and its not in the book. i thought that the sum of F_h and F_g would give me F_t but that's not it, the answer 7.3e-3 N and i don't know how to get there, some help would be apreciated :)