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Dancers experience large forces associated with the jumps they make. For example, when a dancer lands after a vertical jump, the force exerted on the head by the neck must exceed the head?s weight by enough to cause the head to slow down and come to rest. The head is about 9. 4% of a typical person?s mass. Video analysis of a 64 kg dancer landing after a vertical jump shows that her head slows down from 4. 2 m/s to rest in a time of 0. 21 s.

Respuesta :

Compared with the force her neck exerts on her head during landing, the force that head exerts on her neck is 1845.76 N. Deceleration is same during first half and second half and hence force will also be same.

What is force?

In physics, an influence that change the motion of an object is called force.

The head decelerates from 4 m /s to zero in .21 sec ;

Deceleration = (4 - 0) / 0.21

= 19.04 m/s²

If F is the average force, then

F - mg = ma

So Force, F = m ( g + a )

= 64 ( 9.8 + 19.04 )

F = 1845.76 N.

This force will be uniformly acting on head in the upward direction . Therefore deceleration is same during first half and second half and hence force F will also be same.

To know more about force, refer

https://brainly.com/question/12785175

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