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A force of 24 N acts on a body of mass 6 kg for 4 s. Assuming the body to be initially at rest. Then (A) When the force stops acting its velocity is 16 m/s (B) The distance covered in 10 s after the force acting is 128 m (C) The distance covered in 5 s after the force stops acting is 96 m (D) Its momentum after 10 s is 96 kg ms The correct option(s) is/are i)Only Bii)Only Aiii) Both (B) and (D) iv) (A), (B) and (D) if you answer correctly I will make you as brillianest!!! |
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Answer» Force = 4 N., Mass = 2 kg. Using the Formula, F = ma , a = F/m a = 4/2 a = 2 m/s² Now, U = 0 t = 4 seconds v - u = at ⇒ v - 0 = 2 × 4 ⇒ v = 8 m/s. Now, v² - u² = 2aS 64 = 2 × 2 × S S = 16 m. It is the distance covered in FIRST 4 seconds. Now, for the distance covered in another 6 seconds. u = v of above = 8 m/s. t = 10 - 4 = 6 seconds. a = 0 [Force is not ACTING now] S = ut + 1/2at² ∴ S = 8 × 6 + 0 ∴ S = 48 m. Total distance covered in 10 seconds = 16 + 48 = 64 m. |
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