What?

A massless string of length $R$ is there. It starts doing a vertical motion.

If the length of the purple line is $R \cos \theta$ , that means the string's length is reduced, but where does it go?

#Mechanics

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Comments

Length of the purpul line will remain R, why should it change to $R \cos \theta$ ?

Rohit Gupta - 4 years, 4 months ago

I edited the note . We do vertical motion problem by ignoring Rsin(theta) , yeah I know Rsin(theta) is horizontal component and we are doing "vertical" motion . Calculation of h gives a strong feeling that the string becomes short .

Saraswati Sharma - 4 years, 4 months ago

The length of the purple line is still R. The length of the red line above h is $R \cos \theta$ . The total length of the red line and purple line are equal to R.

Rohit Gupta - 4 years, 4 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$