First slide

Relative motion in 2 dimension

Question

Twelve persons are initially at 12 corners of a regular polygon of 12 sides of side a. Each person now moves with a uniform speed v in such a manner that 1 is always directed towards 2,2 towards 3, 3 towards 4, and so on. The time after which they meet is

Moderate

A

$\frac{v}{a}$
B

$\frac{2 a}{v}$
C

$\frac{2 a}{v (2 + \sqrt{3})}$
D

$\frac{2 a}{v (2 - \sqrt{3})}$

Solution

$\begin{array}{l} t = \frac{a}{v - vcos \frac{π}{n}} \cdot Here n = 12 \\ \Rightarrow t = \frac{a}{v - vcos \frac{2 π}{12}} = \frac{2 a}{v (2 - \sqrt{3})} \end{array}$

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App