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Angular distance question - how to solve

  • #1
Poster has been reminded to post schoolwork in the Homework Help forums and show their work
during knee flexion of a squat phase the knee moves from 180 degrees to 95 degrees. if you perform 10 complete squats what is the total angular distance (in radians and in degrees), undergone at the knee?

anyone know how to solve this one? can you explain
 

Answers and Replies

  • #2
115
8
If I understood it correctly:
-If you pay regard to the sign, then 0deg and 0rad.
-If you only count one direction, then 10*(180-95)=850deg=14,84 rad.
 
  • #3
If I understood it correctly:
-If you pay regard to the sign, then 0deg and 0rad.
-If you only count one direction, then 10*(180-95)=850deg=14,84 rad.
that is the answer i got, but the answer key has 1700 degrees for total distance and 29.67 rad. so i was not sure if i was missing something here.
 
  • #4
that is the answer i got, but the answer key has 1700 degrees for total distance and 29.67 rad. so i was not sure if i was missing something here.
here is the sheet if you want to look it
 

Attachments

  • #5
115
8
Then they calculated both directions, without looking at the signs. Yes, this is indeed the third possibility :)
 
  • #6
but why calculate both directions? so in essence, it is 850 x 2 = 1700. Do you know when you have to calculate both directions?
 
  • #7
115
8
I don’t know… really… I only know the physics part… Probably if you want to calculate how much your knee was ‘used’
 
  • #8
SammyS
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but why calculate both directions? so in essence, it is 850 x 2 = 1700. Do you know when you have to calculate both directions?
This is the angular analog of linear distance.

If you walk 1 mile to the store and then back home every day for a week, what is the total distance you walk?

You count the distance both there and back, and then add those for 7 days.
 
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