Physics-

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### Question

#### Two small particles of equal masses start moving in opposite directions from a point A in a horizontal circular orbit. Their tangential velocities are respectively, as shown in the figure. Between collisions, the particles move with constant speeds. After making how many elastic collisions, other than that at ,these two particles will again reach The point

- 4
- 3
- 2
- 1

#### The correct answer is: 2

#### A s first collision one particle having speed 2v will rotate

while other particle having speed will rotate

At first collision they will exchange their velocities. Now as shown in figure, after two collisions they will again reach at point A.

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