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Which one of the following equations related to the motion of an object is NOT correct? (Symbols carry their usual meanings)

Options

  1. As = ut + 1 2 at^2
  2. Bu = v - at
  3. Cu^2 - v^2 = 2as
  4. DDistance travelled during n^ th second = u + 1 2 a(2n-1)

Correct answer

C. u^2 - v^2 = 2as

Step-by-step solution

The standard equations of motion for an object moving with constant acceleration are: v = u + at u = v - at s = ut + 1 2 at^2 v^2 - u^2 = 2as S_n = u + 1 2 a(2n-1) Comparing these with the given options: Option (1) matches the second equation of motion. Option (2) is a valid rearrangement of the first equation of motion. Option (3) is given as u^2 - v^2 = 2as , which contradicts the third equation of motion v^2 - u^2 = 2as . Thus, it is incorrect. Option (4) correctly gives the displacement in the n^ th second. The

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