.Calculating Power Output of 1.8-g Spider

AI Thread Summary
To calculate the power output of a 1.8-g spider walking at 2.3 cm/s up a windowpane at a 25-degree angle, the formula used is P = W/t = Fv cos(θ). The force is determined by F = mg, where m is the mass of the spider and g is the acceleration due to gravity. The initial calculation yielded 0.00037 W, but it was noted that the angle must be considered in the calculation. The corrected formula incorporates the cosine of the angle, leading to a more accurate power output. Properly accounting for the angle is essential for an accurate result.
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Homework Statement


Calculate the power output of a 1.8-g spider(the black dot) as it walks up a windowpane at 2.3 cm/s. The spider walks on a path that is at 25^{o} to the vertical as illustrated below.

http://img19.imageshack.us/img19/4107/spiderl.jpg

Homework Equations


P = W/t
F = mg

The Attempt at a Solution


P= W/t = Fd/t = Fv cos \theta = mgv cos 25 = (0.0018 kg)(9.81 m/s^2)(0.023 m/s) cos25 = 0.00037 W.

Is this correct?

Thanks
 
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While calculating the power you have not considered the angle given in the problem.
So W = F*v*cos(theta)
 
I have actually just editted my post after realizing this.
 
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