Basic Biomechanics
7th Edition
ISBN: 9780073522760
Author: Susan J Hall
Publisher: McGraw-Hill Education
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Textbook Question
Chapter 14, Problem 6AP
The patellar tendon attaches to the tibia at a 20° angle 3 cm from the axis of rotation at the knee. If the tension in the tendon is 400 N, what is the resulting acceleration of the 4.2-kg lower leg and foot given a radius of gyration of 25 cm for the lower leg/foot with respect to the axis of rotation at the knee? (Answer: 15.6 rad/s2)
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Students have asked these similar questions
2. a) Label the system provided below, including the reference frame, moment arms and vector forces
with the information provided.
Internal moment arm = 4cm +0.04m
External moment arm relative
to the segment weight = 25cm 0.25m
External moment arm relative
to the load weight = 45cm 40.45m
Segment weight = 50 N
Load weight = 100 N
Lower leg segment angle relative
to horizontal plane = 45°
Quadriceps tendon angle = 45°
Axis of
rotation
MF
SW
LW
2b) Using the figure in 2a., calculate the external torque of the system relative to the normal
component of segment and load weights listed above.
2c) Calculate the amount of both the tangential component of the muscle force and the muscle force
itself required to keep this system in a state of static equilibrium.
ney:
Load (L) = 5 kgs
= Effort
E = Fulcrum
Weight of forearm = 1.8 kgs
L = Load
Biceps brachii
muscle
Distance of load from elbow joint = 35 cm
%3D
Effort (E) = contraction
of biceps brachii
Distance of center of mass of forearm from elbow = 17 cm
Distance of tendon from elbow = 4 cm
A) Draw the free-body diagram to represent the forces and moments
Load (L) = weight of
object plus forearm
B) Write the torque equation for static equilibrium
Fulcrum (F) = elbow joint
Total compressive knee forces range between
O 1-2 %BW
O 2-4 %BW
3-5 %BW
0.5-1.5 %BW
Chapter 14 Solutions
Basic Biomechanics
Ch. 14 - If you had to design a model of the human body...Ch. 14 - Construct a table displaying common units of...Ch. 14 - Skilled performance of a number of sport skills is...Ch. 14 - Prob. 5IPCh. 14 - How much angular impulse must be supplied by the...Ch. 14 - Given the following principal transverse axis...Ch. 14 - A volleyball players 3.7-kg arm moves at an...Ch. 14 - A 50-kg diver in a full layout position, with a...Ch. 14 - Prob. 10IPCh. 14 - The radius of gyration of the thigh with respect...
Ch. 14 - A 0.68-kg tennis ball is given an angular momentum...Ch. 14 - A 7.27-kg shot makes seven complete revolutions...Ch. 14 - Prob. 5APCh. 14 - The patellar tendon attaches to the tibia at a 20...Ch. 14 - A cavewoman swings a 0.75-m sling of negligible...Ch. 14 - A 7.27-kg hammer on a 1-m wire is released with a...Ch. 14 - Discuss the effect of banking a curve on a...
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Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, bioengineering and related others by exploring similar questions and additional content below.Similar questions
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