Need Help Magnitude and Forces problem

In summary, the free body diagram depicts a runner running around a turn on a track. The approximate lean a runner would have while running at their maximum speed is estimated, along with estimates of the relative distances between the runner's mass center and the various forces depicted in the free body diagram. The magnitudes of the forces depicted in the free body diagram are estimated. Finally, equations are used to calculate the direction and magnitude of the moments produced about the mass center by each of the forces depicted in the free body diagram. A drawing is made showing the forces involved, and the runner's overhead view is used to calculate the mv2/R. Finally, the side force that needs to be offset is identified.
  • #1
sfs007
3
0
Need Help ASAP! Magnitude and Forces problem

Homework Statement




Based on a free body diagram of a runner running around a turn on a track:

1. An estimate of the lean you would have while running at your maximum speed on a university track and
2. estimates of the relative distances between your mass center and the various forces depicted in the free body diagram, and
3. an estimate of the magnitudes of the forces depicted in the free body diagrams,

You should:
Calculate the magnitudes and directions of the moments produced about the mass center by each of the forces shown in the free body diagram. The moment magnitudes should be given with appropriate units or dimensions.

Weight is 150lbs or 68kg
Height is 5'8
 
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  • #2


sfs007 said:

Homework Statement

Based on a free body diagram of a runner running around a turn on a track:

1. An estimate of the lean you would have while running at your maximum speed on a university track and
2. estimates of the relative distances between your mass center and the various forces depicted in the free body diagram, and
3. an estimate of the magnitudes of the forces depicted in the free body diagrams,

You should:
Calculate the magnitudes and directions of the moments produced about the mass center by each of the forces shown in the free body diagram. The moment magnitudes should be given with appropriate units or dimensions.

Weight is 150lbs or 68kg
Height is 5'8

Welcome to PF.

What would be your attempt at a solution?
 
  • #3


I don't know where to start. I am in grad school for Health promotion and this is a biomechanics class which I know nothing about
 
  • #4


sfs007 said:
I don't know where to start. I am in grad school for Health promotion and this is a biomechanics class which I know nothing about

What is the radius of the track?

When you are traveling around a curve what is the radial force? MV2R.
http://hyperphysics.phy-astr.gsu.edu/hbase/cf.html#cf

What weight shift do you need to compensate for that? That would be the centrepital force you need to balance. You balance that with your weight shifted how far? Draw a diagram and figure how to balance with the foot as a pivot. Weight down times shift must be Centripetal force times the height of the Center of mass away from the foot.
 
  • #5


still lost me!
 
  • #6


sfs007 said:
still lost me!

Sorry, I can't do the problem for you.

Look at the equations.

Make a drawing of the forces involved, the runner overhead to figure the mv2/R and then head on and identify the side force you just calculated and how shifting the weight from over the center of mass can offset it.
 

1. What is the difference between magnitude and force?

Magnitude refers to the size or amount of a physical quantity, such as distance or speed. Force, on the other hand, is a vector quantity that describes the push or pull on an object. Magnitude does not have a specific direction, while force does.

2. How do you calculate magnitude and forces in a problem?

To calculate magnitude, you simply find the absolute value of the physical quantity. For forces, you need to consider both magnitude and direction. This can be done using mathematical equations such as Newton's Second Law of Motion (F=ma) or vector addition.

3. Can magnitude and forces be negative?

Yes, both magnitude and forces can be negative. A negative magnitude simply indicates that the direction is opposite to the conventional positive direction. Negative forces indicate a push in the opposite direction of the conventional positive direction.

4. How does the magnitude of a force affect an object?

The magnitude of a force determines the amount of acceleration an object experiences. The greater the force, the greater the acceleration. Additionally, the direction of the force also plays a role in determining the overall motion of the object.

5. Are there any real-life examples of magnitude and forces?

Yes, there are many real-life examples of magnitude and forces. For instance, the weight of an object is an example of a magnitude, and the force of gravity acting on that object is an example of a force. Other examples include a car accelerating due to the force of the engine and a ball falling towards the ground due to the force of gravity.

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