A child is riding in a child-restraint chair, securely fastened to the seat of a car. Assume the car has speed 49 km/h when it hits a tree and is brought to rest in 0.20 s. The mass of the child is 18 kg . Assuming constant deceleration during the collision, estimate the net horizontal force F that the straps of the restraint chair exert on the child to hold her in the chair. Express your answer to two significant figures and include the appropriate units. Enter positive value if the direction of the force is in the direction of the initial velocity and negative value if the direction of the force is in the direction opposite to the initial velocity.

A child is riding in a child-restraint chair, securely fastened to the seat of a car. Assume the car has speed 49 km/h when it hits a tree and is brought to rest in 0.20 s. The mass of the child is 18 kg . Assuming constant deceleration during the collision, estimate the net horizontal force F that the straps of the restraint chair exert on the child to hold her in the chair. Express your answer to two significant figures and include the appropriate units. Enter positive value if the direction of the force is in the direction of the initial velocity and negative value if the direction of the force is in the direction opposite to the initial velocity.

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter5: Newton's Laws Of Motion

Section: Chapter Questions

Problem 49PQ: A block with mass m1 hangs from a rope that is extended over an ideal pulley and attached to a...

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