Dynamic Analysis of Motion - Biomechanics

[kreuzberg]

Homework Statement

A leg has a horizontal propulsive ground reaction force 200N and vertical ground reaction foce of 1200N applied to it. Draw a free body diagram. The leg has an acceleration of -4m/s2 in the x direction and 8m/s2 in the y direction. What are the horizontal + vertical components of the force acting across the hip? What is the total force across the hip?

Homework Equations

F=MA

The Attempt at a Solution

Hi, I have read the community guidelines specifying that you need to show your own attempt. I wish I could but I really have no idea how to do this question. Could someone guide me with how to approach this question? All help would be appreciated. :)

 

[tiny-tim]

welcome to pf!

hi kreuzberg! welcome to pf!

treat the leg as a separate body

draw a free body diagram for it …

there will be the two given forces at the bottom of the leg (the ground), and two unknown forces (cal them H and V) at the top (the hip)

(technically, there's also the weight of the leg itself, acting vertically at the middle of the leg, but i think that's so small that you're expected to ignore it )

apply F = ma (i think you'll need to know the mass of the leg) …

what do you get? ​