If a be the acceleration of the body, then distance travelled by the body in 2s is given as. xi=ut+
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at2=0×2+
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a×(2)2 x1=2a....(i) Velocity of body at the end of 2s is given as. v=u+af=0+a×2 v=2a ....(ii) Distance travelled by the body in next 2 s is given as. x2=vt+
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at2 =2a×2+
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a×(2)2[ from Eq. (ii) ] =4a+2a x2=6a=3×2a ⇒x2=3×x1 [from Eq. (i)] ⇒x2=3x1