Calculating amount of compression a bone can withstand

  • Thread starter Thread starter sruthis
  • Start date Start date
  • Tags Tags
    Compression
AI Thread Summary
To calculate the amount of compression a bone can withstand, the stress equation (stress = elastic modulus x strain) is essential. The Young's modulus for bone is approximately 18 x 10^9 Pa, and it can endure a maximum stress of 160 x 10^6 Pa before failure. The discussion highlights the importance of understanding the relationship between stress, strain, and the change in length of the bone. Participants emphasize the need to carry units through calculations to avoid errors. Ultimately, recognizing that stress is defined as force per area simplifies the problem-solving process.
sruthis
Messages
7
Reaction score
0
Please I need help with this question. I know I have to use the stress = elastic modulus x strain equation, but i do not know how to apply it to this particular problem.


A Bone has a young's modulus of about 18 x 10^9 Pa. Under compression, it can withstand a stress of about 160 x 10^6 Pa before breaking. Assume that a femur (thighbone) is 0.50 m long, and calculate the amount of compression this bone can withstand before breaking.
 
Physics news on Phys.org
Hi sruthis, welcome to PF. In this problem, what is the elastic modulus? What is the stress? How is strain related to change in length? You have the right equation, now you just need to apply it correctly. Try to carry the units along with the numbers to avoid making an error.
 
I think I need to somehow use the equation F/A = Y(change in L/Linitial) and solve for Linitial, and i guess plug that value into the stress equation? but i do not know how to find A, and I am not sure if I have the right idea.
 
You're already given the stress, you don't need to find it by dividing force by area.
 
ohh. thank you so much. i completely did not realize that F/A was the stress. Thank you thank you.
 
Thread 'Struggling to make relation between elastic force and height'

Thread 'Struggling to make relation between elastic force and height'

Hello guys this is what I tried so far. I used the UTS to calculate the force it needs when the rope tears. My idea was to make a relationship/ function that would give me the force depending on height. Yeah i couldnt find a way to solve it. I also thought about how I could use hooks law (how it was given to me in my script) with the thought of instead of having two part of a rope id have one singular rope from the middle to the top where I could find the difference in height. But the...
View full post »
Thread 'Voltmeter readings for this circuit with switches'

Thread 'Voltmeter readings for this circuit with switches'

TL;DR Summary: I would like to know the voltmeter readings on the two resistors separately in the picture in the following cases , When one of the keys is closed When both of them are opened (Knowing that the battery has negligible internal resistance) My thoughts for the first case , one of them must be 12 volt while the other is 0 The second case we'll I think both voltmeter readings should be 12 volt since they are both parallel to the battery and they involve the key within what the...
View full post »

Similar threads

Compression of human bone: forces
Replies
2
Views
6K
Confusion Calculating Young's Modulus
Replies
5
Views
2K
Basic Stress and Strain question -- Rock on top of a vertical column
Replies
19
Views
2K
Femur Compression/Young's Modulus
Replies
7
Views
16K
How Much Force Can a Human Femur Withstand Before Breaking?
Replies
2
Views
9K
Finding out distance before breaking leg using Hooke's Law
Replies
1
Views
4K
What is the Maximum Temperature for a Copper Block at 1000 atm Pressure?
Replies
3
Views
3K
Young's Modulus and the Poisson Ratio of Aluminium
Replies
1
Views
2K
Calculating Young's Modulus from this Stress/Strain Graph
Replies
29
Views
7K
Different young modulus of rod - Need a proper explanation?
Replies
2
Views
2K

Hot Threads

Recent Insights

Back
Top