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JEE Main2006MathematicsVector AlgebraActual

A particle has two velocities of equal magnitude inclined to each other at an angle . If one of them is halved, the angle between the other and the original resultant velocity is bisected by the new resultant. Then is

Options

  1. A90^
  2. B120^
  3. C45^
  4. D60^

Correct answer

B. 120^

Step-by-step solution

4 = u 2 u+ u 2 4 + 1 2 4 = 1 2 4 2 4 = 3 4 =3 4 -4 ^3 4 ^2 4 = 1 4 4 =30^ or =120^

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