# Indian Rope Trick

This string appears to be held up by nothing at all!

The plastic pieces help to provide tension in the string, but where is the support coming from? All of these are otherwise flimsy materials

What is the maximum height that this string can stretch out to? What would your answer depend on?

Note by Chung Gene Keun
7 years, 2 months ago

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I agree with Pinak.

The plastic is in a deformed state and hence will tend to become straight.

It has been connected with the help of knots, the force that the plastic exerts on the knots will result in a tension in the rope.

The entire system can be thought of as a spring having some mass.

The maximum height will depend on the effective spring constant, (which will depend on the elasticity constant of the plastic and the string, if it is extensible) and the total mass.

- 7 years, 2 months ago

Astute.

- 7 years, 2 months ago

The potential energy stored in the plastic when it is bent?

Just like a spring will support mass when compressed.

- 7 years, 2 months ago

9.8 metres....equilibrium of deformed string

- 7 years, 2 months ago

total height achieved should depend on the mass of the string, the stiffness of the plastic pieces.... .....oh, n the length of the string :)

- 7 years, 2 months ago

The stress generated in the plastic due to tensile force is providing the rope required tension.

- 7 years, 2 months ago

spring constant

- 7 years, 2 months ago

Height depends on base .and the trick based on force against force.

- 7 years, 2 months ago