How to figure out how many 250 g geckos could be suspended for the ceiling by a single foot pad? Given foot pad area 1.0 cm^2 while it can attach to a wall or ceiling with a force of 11 N.

Question

anonymous · Answer

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Each gecko has a gravitational force on it equal to the mass(in kg)*g (g=9.8 m/s^2), which is a force of 2.45N.  Because they are not moving the vertical forces must cancel out, which means that the tension on the rope is equal to the gravitational force.  And the rope has the same tension in both directions, so it pulls on the pad with a force of 2.45 N.

I'm not really sure how to incorporate the area of the foot pad, but neglecting that, the pad would be able to hold 11N/2.45N geckos, or 4.48, which must be rounded down to 4 because you can't have half a gecko.