Dancers experience large forces associatedwith the jumps they make. For example, when a dancer landsafter a vertical jump, the force exerted on the head by the neck mustexceed the head’s weight by enough to cause the head to slow down andcome to rest. The head is about 9.4% of a typical person’s mass. Videoanalysis of a 65 kg dancer landing after a vertical jump shows that herhead decelerates from 4.0 m>s to rest in a time of 0.20 s. While the dancer is in the air and holding a fixed pose, what is the magnitude of the force her neck exerts on her head? (a) 0 N; (b) 60 N; (c) 120 N; (d) 180 N.

Dancers experience large forces associatedwith the jumps they make. For example, when a dancer landsafter a vertical jump, the force exerted on the head by the neck mustexceed the head’s weight by enough to cause the head to slow down andcome to rest. The head is about 9.4% of a typical person’s mass. Videoanalysis of a 65 kg dancer landing after a vertical jump shows that herhead decelerates from 4.0 m>s to rest in a time of 0.20 s. While the dancer is in the air and holding a fixed pose, what is the magnitude of the force her neck exerts on her head? (a) 0 N; (b) 60 N; (c) 120 N; (d) 180 N.

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