What is the Direction of Force in a Falling Object's Free-Body Diagram?

  • Thread starter Thread starter Ascendant78
  • Start date Start date
  • Tags Tags
    Dynamic Forces
Click For Summary
SUMMARY

The discussion centers on the free-body diagram of a 40kg person falling under the influence of gravity, which accelerates at 9.8 m/s². The gravitational force acting on the person is calculated as F(gravity) = -392N, indicating that the force is directed downward, or in the negative direction. The conversation clarifies that while the force is negative in terms of direction, it is often expressed as a positive magnitude when discussing forces. This distinction is crucial for understanding vector quantities in physics.

PREREQUISITES
  • Understanding of Newton's laws of motion
  • Familiarity with free-body diagrams
  • Basic knowledge of vector quantities
  • Ability to perform calculations involving force and mass
NEXT STEPS
  • Study vector representation of forces in physics
  • Learn about Newton's second law of motion and its applications
  • Explore the concept of net force and its implications in free-body diagrams
  • Investigate the effects of air resistance on falling objects
USEFUL FOR

Students studying physics, educators teaching mechanics, and anyone interested in understanding the principles of force and motion in free-body diagrams.

Ascendant78
Messages
327
Reaction score
0

Homework Statement



A 40kg person is falling at the speed of gravity, 9.8m/s^2. Wind resistance is not considered. On your free-body diagram, the direction they are falling (ground) is in the negative direction, hence gravity is causing an acceleration in the negative.

Homework Equations



F(gravity) = (40)(-9.8)
F(gravity) = -392N

The Attempt at a Solution



I am simply curious when solving a problem such as this, would N be a -392N since it is traveling in the negative on the free-body diagram, or is it seen a magnitude and considered a positive number?
 
Physics news on Phys.org
Ascendant78 said:
I am simply curious when solving a problem such as this, would N be a -392N since it is traveling in the negative on the free-body diagram, or is it seen a magnitude and considered a positive number?

Force is a vector therefore it has a direction. Also the direction of the movement of the object and the direction of the force do not have to me the same. For example a ball going up after you throw it moves up but the force acting on it is downward.
 
Thank you.
 

Similar threads

Potential Mistake in Free-Body Diagram
  • · Replies 5 ·
Replies
5
Views
2K
Is it friction or tension acting on the person hanging on a rope?
  • · Replies 4 ·
Replies
4
Views
1K
Block on top of an inclined plane, with a rough surface, that moves with constant acceleration
  • · Replies 41 ·
2
Replies
41
Views
4K
Maximum force applied to prevent block from sliding up ramp
  • · Replies 11 ·
Replies
11
Views
2K
Finding Radial Force from Free Body Diagram
  • · Replies 4 ·
Replies
4
Views
2K
Forces and Free-Body Diagrams in Real-World Scenarios
  • · Replies 5 ·
Replies
5
Views
4K
What are the equations for circular motion on a Ferris wheel with R2D2?
  • · Replies 12 ·
Replies
12
Views
2K
Resistance force changing the velocity of an object
  • · Replies 8 ·
Replies
8
Views
1K
Analyzing Forces & Electrons: Free Body Diagram
  • · Replies 2 ·
Replies
2
Views
2K
Angular acceleration of plank hanging off edge with a weight
  • · Replies 7 ·
Replies
7
Views
2K