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JEE Main202116 Mar 2021Evening ShiftPhysicsMotion in One DimensionActual

A body of mass 2 kg moves under a force of 2 i ^ + 3 j ^ + 5 k ^ N It starts from rest and was at the origin initially. After 4 s , its new coordinates are 8 , b , 20 . The value of b is ______. (Round off to the Nearest Integer)

Correct answer

0

Step-by-step solution

a → = F → m = 2 i ^ + 3 j ^ + 5 k ^ 2 = i ^ + 1 . 5 j ^ + 2 . 5 k ^ τ → = u → t + 1 2 a → t 2 = 0 + 1 2 i ^ + 1 . 5 j ^ + 2 . 5 k ^ 16 = 8 i ^ + 12 j ^ + 20 k ^ b = 12

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