A wire forming a loop is dipped into soap solution and taken out,so that a film of soap solution is formed. a loop of 6.28cm long thread is gently put on the film and the film is wingspaned with a needle inside the loop. the thread loop takes the shape of a circle.
Find the tension in the thread. Surface tension of soap solution=0.30N/m.

Question

A wire forming a loop is dipped into soap solution and taken out,so that a film of soap solution is formed. a loop of 6.28cm long thread is gently put on the film and the film is wingspaned with a needle inside the loop. the thread loop takes the shape of a circle.
Find the tension in the thread. Surface tension of soap solution=0.30N/m.

anonymous · Answer

@LastDayWork

anonymous · Answer

like this? :P https://www.youtube.com/watch?v=e0fhh1830Kc |dw:1393851663668:dw| That's how the surface tension force is acting.. now you know how much the surface tension is (which is nothing but force/unit length) so all you need is the length of that loop (which is given).. so what would be to total force acting on that looP ?