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A 63 kg boy and a 37 kg girl use an elastic rope while engaged in a tug-of-war on a frictionless icy surface. if the acceleration of the girl toward the boy is 2.3 m/s 2 , determine the magnitude of the acceleration of the boy toward the girl. answer in units of m/s 2 .

Respuesta :

From Newton's third law of motion, the force that is exerted to the boy must be the same force exerted to the girl only that the direction is opposite. The net force in this item is,

   F = m x a 
Girl:
  F = (37 kg)(2.3 m/s²)
   F = 85.1 N

In the boy's case,
   F = m x a
   a = F/m

Boy:
  a = 85.1 N/63 kg
   a = 1.35 m/s²

Answer: 1.35 m/s²