Wording of a Force and Motion problem

  • Thread starter Thread starter Beamsbox
  • Start date Start date
  • Tags Tags
    Force Motion
Click For Summary
SUMMARY

The discussion centers on the wording of a physics problem involving a firefighter sliding down a pole, specifically regarding the forces acting on and by the firefighter. The problem presents two pairs of questions: one set asking for the magnitude and direction of the vertical force on the firefighter from the pole, and the other set asking for the force exerted by the firefighter on the pole. The participant concludes that the book's wording is misleading, as it conflates the forces according to Newton's Third Law, which states that for every action, there is an equal and opposite reaction. The participant identifies the upward force exerted by the pole on the firefighter as 494N and asserts that the questions are fundamentally asking for the same information.

PREREQUISITES
  • Understanding of Newton's Third Law of Motion
  • Basic knowledge of force and motion concepts
  • Familiarity with vector forces and their directions
  • Ability to interpret physics problems and their wording
NEXT STEPS
  • Review Newton's Third Law of Motion and its applications in force problems
  • Practice solving force diagrams involving multiple forces
  • Explore common pitfalls in physics problem wording and interpretation
  • Study examples of force interactions in real-world scenarios, such as friction and tension
USEFUL FOR

Students studying physics, educators preparing problem sets, and anyone interested in improving their understanding of force interactions and problem-solving in mechanics.

Beamsbox
Messages
61
Reaction score
0
These are my forte... questions that make you feel dumb when you spend 20 minutes just thinking about what the hell they're asking... and then make you feel dumber once you figure out the simplicity of the answer...

Here we go, this has to do with the wording of the problem. To me a) and b), ask the same thing as c) and d)... but apparently I'm wrong.

Firefighter (712N) sliding down a pole...

a) asks for the magnitude and b) asks for the direction "of the vertical force on the firefighter from the pole."

c) asks for the magnitude and d) asks for the direction "of the vertical force of the pole on the firefighter."

I have figured out a) and b), b) being upwards. [a) is 494N which I'll reference later.]
The book says that c) has the same magnitude as a), but that d) is in the opposite direction (down).

Now I have looked at the problem like this:
a) and b) are asking about the force that the pole is exerting on the firefighter, and since it is slowing him down, it would be in the upwards direction.

Say that c) and d) are asking for the force that the firefighter exerts on the pole (I assume this because the answer says that the direction is down), this makes sense because the force the firefighter exerts on the pole would equal the force the pole exerts on the firefighter, and as a system, the remaining force is what propels the downward motion (that left over from the restriction of the upward force against the gravity).

Am I wrong to way that the book has worded this question correctly, and that the quoted and underlined sentences above are asking for the same information?

Thanks all!
 
Physics news on Phys.org
The wording is clearly wrong.
I'm sure the question meant to ask you about the Newton's 3rd Law pair of forces.
One is the vertical force of the pole on the firefighter, and the other is the vertical force of the firefighter on the pole.
 
Thank you, I thought I was crazy on this one.
 

Similar threads

  • · Replies 10 ·
Replies
10
Views
3K
  • · Replies 11 ·
Replies
11
Views
1K
  • · Replies 8 ·
Replies
8
Views
19K
  • · Replies 30 ·
2
Replies
30
Views
2K
Replies
16
Views
1K
  • · Replies 6 ·
Replies
6
Views
2K
Replies
3
Views
3K
Replies
4
Views
5K
  • · Replies 10 ·
Replies
10
Views
2K
  • · Replies 5 ·
Replies
5
Views
1K