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JEE Main20206 Sep 2020Evening ShiftPhysicsMotion in One DimensionActual

When a car is at rest, its driver sees rain drops falling on it vertically. When driving the car with speed v , he sees that rain drops coming at an angle 60 ∘ from the horizontal. On further increasing the speed of the car to 1 + β v , this angle changes to 45 ∘ . The value of β is close to :

Options

  1. A0 . 50
  2. B0 . 41
  3. C0 . 37
  4. D0 . 73

Correct answer

D. 0 . 73

Step-by-step solution

tan = 60 ° = v rg v ........ 1 tan 45 ° = v rg ( β + 1 ) v .......... 2 3 v = ( β + 1 ) v β = 3 - 1 = 0 . 732

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