Understanding Forces in the Body: A Homework Challenge

In summary: It is also harder for someone who does not understand the material to fake.In summary, the user is a new member seeking help with a homework problem on forces in the body. They have attached the problem and are asking for assistance with the first question. They have attempted to solve the problem and are not sure if their answer is correct. The user is also asking for an explanation that is not too difficult to understand. The conversation then delves into a discussion about torque, the relationship between torque and force, and the units for torque. The user is reminded to show their thought process when asking for help and to clarify the point about taking torque in the problem.
  • #1
Shanghai Babe
6
0
hey everybody :) i am new here and i need ur help. I have to solve this problem for home work tomorrow.Topic is forces in the body.

I attached it. I actually need help for the whole first question.
thx u in advance.
Please try to explain it not too difficulty. thanks u :)

Homework Statement





Homework Equations














The Attempt at a Solution

 

Attachments

  • Biophysics- quiz forces in the body.jpg
    Biophysics- quiz forces in the body.jpg
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  • #2
Hi! As per the forum guidelines, you need to show us your attempt at the solution before we can help you. What have you tried so far? Where are you getting stuck?
 
  • #3
To get the best from this forum, you should show us your best attempt.
For that problem (1a) you put axis on the diagram and use your knowledge of trigonometry.
 
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  • #4
i already tried to calculate it. for 1a) i got 17,10N as result. but i am not sure if its right. I calculated : 50xcos70.
 
  • #5
@ Simon Bridge spare me the comment! if u don't want to help don't reply!
 
  • #6
for 1b i got : 50xsin70=46,98 T
 
  • #7
@ Simon Bridge spare me the comment! if u don't want to help don't reply!
I cannot help without knowing how you are thinking about the problem.
From the information you supplied, you got a fair comment: but it's a bit terse. I edited so it reads more clearly. Better?

Your numbers don't mean anything - I need to see your reasoning: how are you thinking about the problem.
From what you have written I can make a guess about this - but it is unlikely to be very satisfying for you.

I wonder if you have misunderstood the nature of this place? We can help a student get unstuck but we do not do the work for the student. This creates a problem when someone asks "is this the right answer?" If I just say "yes" or "no" then some students will be cunning and keep guessing until I say "yes" and so get the right answer by making me do the work.

But it appears you can apply the rules of trigonometry OK :)
If ##\theta## is the angle some force ##\vec{F}## to the horizontal, then the horizontal component of that force is, indeed, ##F\cos(\theta)##

You kept going:

for 1b i got : 50xsin70=46,98 T
You appear to have computed the vertical component of T.
Is that correct?

1b asks for torque
... what is torque?
... what are the units for torque?

For (c) you have already asked in another thread.
But you already know - just consider what the term "translational equilibrium" means.
If in doubt, you can look in your class notes or use google ;)

For (d) it is the same process, but for rotation.
 
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  • #8
i am not here for the pupose that people are doing my homework. i don't understand what u meant by " what are you thinking about this problem".
50xcos70=17,10N

50 stands for the force (which is given) and 70( is given too) for the angle.

relating to 1b)
torque is the tendency of a force to rotate the body to which it is applied. torque is always specified with the regard to the axis rotation.relationship betwenn torque and force is : Torque=F(force)x R (radius or distance ) unit of torque is Newtonmeters.
 
  • #9
Shanghai Babe said:
torque is always specified with the regard to the axis rotation.
It is meaningful (but not always useful) to take the torque about any point. Standing on one end of a non-uniform horizontal beam, each point of the beam is a potential break point, so your torque about each point is worthy of consideration.
The question is a little deficient here. It ought to specify the point to take the torque about, but presumably it means O.
relationship betwenn torque and force is : Torque=F(force)x R (radius or distance ) unit of torque is Newtonmeters.
Quite so (but to clarify, F and R must be as measured at right angles to each other). You gave as answer 50xsin70 T. Not sure what the T represents in that, so I guess you meant N. But as Simon said, that's the vertical component of T, so it's a force, not a torque. What is the radius here?
 
  • #10
Thanks haruspex: the attachment is a little tricky to read isn't it?
Hmmm... my earlier reply doesn't seem to have been recorded - but it was basically what you said with a description of what it means to "show what you are thinking".

@Shanghai Babe :
When you do a problem, you have to think about it ... you'd normally just do it in your head. In order to help you properly, I need to have some idea about this process. From what you've written I can make guesses ... but that will be unlikely to be very pleasing for you and it takes longer.

One way of showing your thinking is to use more plain language descriptions to go with your math - and use symbols more.

It is a useful skill to learn and it can get you more marks when you use it i assignments.
 

1. What are the main types of forces in the body?

The main types of forces in the body are contact forces and non-contact forces. Contact forces include tension, compression, shear, and friction, while non-contact forces include gravity, electromagnetic forces, and nuclear forces.

2. How do forces affect the human body?

Forces play a crucial role in maintaining the structure and function of the human body. They allow us to move, maintain posture, and perform physical activities. Forces can also cause injuries and impact our overall health and well-being.

3. How do muscles generate forces in the body?

Muscles generate forces through the contraction and relaxation of muscle fibers. When muscles contract, they pull on the bones they are attached to, creating movement and generating forces that allow us to perform tasks and activities.

4. What is the relationship between forces and motion in the body?

Forces and motion are closely related in the body. Forces can cause motion, and motion can also generate forces. For example, when we walk or run, our muscles generate forces that allow us to move, and the impact of our feet hitting the ground creates forces that propel us forward.

5. How can understanding forces in the body be beneficial in everyday life?

Understanding forces in the body can help us prevent injuries and maintain good physical health. By understanding how forces affect our bodies, we can make informed decisions about our movements and activities, leading to better overall well-being.

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