Solving Momentum of a Ball Homework: Man's Speed & Average Force

  • Thread starter Thread starter phizics09
  • Start date Start date
  • Tags Tags
    Ball Momentum
Click For Summary

Homework Help Overview

The problem involves a man throwing a ball while standing on a smooth ice surface, focusing on the concepts of momentum and force. The subject area includes mechanics, specifically the conservation of momentum and the relationship between force and momentum change.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • The original poster attempts to apply conservation of momentum to determine the man's speed after throwing the ball but expresses uncertainty about calculating the average force for multiple throws.

Discussion Status

Some participants offer guidance on using the relationship between force and momentum change, suggesting that the average force can be calculated based on the rate of momentum change with multiple throws. There appears to be a productive exchange of ideas, though no consensus is reached on the final approach.

Contextual Notes

The problem involves specific parameters such as the mass of the man and the ball, as well as the speed of the throw, which may influence the calculations. The discussion reflects the constraints of a homework setting, where complete solutions are not provided.

phizics09
Messages
38
Reaction score
1

Homework Statement


An 80 kg man standing at rest on a smooth, level ice surface throws a 200g ball horizontally with a speed of 25 m/s, relative to the Earth. a) With what speed and in what direction does the man move? b) If the man throws six such balls every 5.0s, what is the average force acting on him?


Homework Equations


Ft=mv


The Attempt at a Solution


I got part a using the conservation of momentum equation, but I don't get how to do b.
Can anyone help?
 
Physics news on Phys.org
Use F = ma = M*Δv/Δt
Every throw gives him a bit of Δv. Multiply it by 6 for 6 throws.
 
Okay, I got it. Thanks!
 
Most welcome!
 
Force = rate of change of momentum
Force = change in momentum per second
Force = change in momentum of each interaction x number of interactions per second
This is another way to say what Delphi51 said.
 
Okay thanks!
 

Similar threads

  • · Replies 9 ·
Replies
9
Views
1K
Replies
1
Views
2K
Replies
9
Views
4K
  • · Replies 19 ·
Replies
19
Views
3K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 62 ·
3
Replies
62
Views
13K
  • · Replies 13 ·
Replies
13
Views
2K
  • · Replies 18 ·
Replies
18
Views
3K
  • · Replies 24 ·
Replies
24
Views
4K
  • · Replies 12 ·
Replies
12
Views
4K