Q1) The quadriceps tendon attaches to the tibia at a 30° angle 4 cm from the joint center at the knee. When an 80 N weight is attached to the ankle 28 cm from the knee joint, how much force is required of the quadriceps to maintain the leg in a horizontal position? When the subject mass is 75 kg, What is the magnitude and direction of the reaction force exerted by the femur on the tibia? (Neglect the action of other muscles.) Note: the case in static condition. Use table 4.1. wt = 80 N dwt = 0.28 m dp = 0.04 m Fm 30 R. 80 N 0.04 m' 0.28 m

Q1) The quadriceps tendon attaches to the tibia at a 30° angle 4 cm from the joint center at the knee. When an 80 N weight is attached to the ankle 28 cm from the knee joint, how much force is required of the quadriceps to maintain the leg in a horizontal position? When the subject mass is 75 kg, What is the magnitude and direction of the reaction force exerted by the femur on the tibia? (Neglect the action of other muscles.) Note: the case in static condition. Use table 4.1. wt = 80 N dwt = 0.28 m dp = 0.04 m Fm 30 R. 80 N 0.04 m' 0.28 m

International Edition---engineering Mechanics: Statics, 4th Edition

4th Edition

ISBN:9781305501607

Author:Andrew Pytel And Jaan Kiusalaas

Publisher:Andrew Pytel And Jaan Kiusalaas

Chapter4: Coplanar Equilibrium Analysis

Section: Chapter Questions

Problem 4.41P: The center of gravity of the 3000-lb car is at G. The car is parked on an incline with the parking...

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