Calculating Force & Accel. From Cell Phone Dropping Homework

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The discussion revolves around a physics homework problem involving a cell phone falling and the subsequent force and acceleration experienced by a kid's head when the phone is stopped by the headphone cord. The mass of the phone is given as 143 grams, and the distance it dropped is 50 centimeters. Participants clarify that the head does not detach but instead experiences a downward jerk when the phone stops. One user seeks confirmation on their calculations related to the force and acceleration affecting the head. The conversation emphasizes the importance of showing work when asking for help in solving physics problems.
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Homework Statement


A hip kid is sitting down listening to music on his cell phone. The ear buds connected to the phone are inserted in his ears firmly and the phone is in his pocket. As the kid pulls something out of his pocket, the phone falls out and freely falls until just centimeters above the ground (irrelevant how far). The phone is stopped as the headphone cord becomes taught. The mass of the phone is 143 grams and the distance the phone dropped was 50 centimeters. The mass of the kid's head was 5 kilograms. Imagining that there is no resistance from the head and the ear buds stay in the ears, answer the following question:


Homework Equations


What was the a) force on the head and b) acceleration of the head?


The Attempt at a Solution


I have a possible answer and just want to check if I am right. Can someone tell me what they get? Thank you.
 
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Hi gembi. Welcome to Physics Forums.

Do I have this right ... the head falls off?
 
No, my professor said that the head just acts like it would in real life. When the phone stops it jerks the head downward a little bit. My professor wants to know the force and acceleration. caused by this
 
I have a possible answer...

You should show your attempt when requesting help/confirmation.
 
NascentOxygen said:
Hi gembi. Welcome to Physics Forums.

Do I have this right ... the head falls off?

:smile::smile:
 
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