Need help with two questions - velocity and momentum?

  • Thread starter Thread starter Renue
  • Start date Start date
  • Tags Tags
    Momentum Velocity
Click For Summary

Homework Help Overview

The discussion revolves around two questions related to velocity and momentum. The first question involves comparing the velocities of two balls, one rolling on a flat surface and the other on an inclined surface. The second question concerns the distance between two people throwing and catching a ball over time.

Discussion Character

  • Exploratory, Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants explore the conditions under which the two balls might have the same velocity, with one suggesting that the gap between the balls indicates their velocity. Questions arise about the definitions of speed and velocity and their implications for the first question.
  • For the second question, participants express confusion regarding the clarity of the question and the assumptions involved, with some questioning the relevance of friction and the lack of initial conditions.

Discussion Status

The discussion is ongoing, with participants seeking clarification on the questions posed. Some have offered insights into the nature of speed versus velocity and the implications for the first question. There is recognition of ambiguity in the second question, with various interpretations being explored.

Contextual Notes

Participants note the absence of specific information such as time, velocity, and initial conditions, which complicates the analysis of both questions. The potential impact of friction on the second question is also under consideration.

Renue
Messages
3
Reaction score
0

Homework Statement


Q1. A ball is rolling on a flat surface and another ball rolling on an inclined surface. When do both the balls have same velocity?
Q2. When two people throw a ball and catch for a period of time, will the distance between them increase, decrease, or remain the same?

Homework Equations


Q1. No equations or numbers given - just t1, t2, etc.
Q2. This is also a conceptual question and no equations or numbers given.

The Attempt at a Solution


Q1. I looked at the space between each ball as it is rolling, wherever the gap was same, I chose that time period as having same velocity.
Q2. The distance would remain the same if the velocity is constant throughout.
Please let me know if my thinking is in the right direction for both these questions. Thanks.
 
Physics news on Phys.org
Renue said:
I looked at the space between each ball as it is rolling, wherever the gap was same, I chose that time period as having same velocity.
What is the difference between speed and velocity?

Q2 is unclear.
 
Speed does not have direction (scalar) and velocity is a vector quantity. How do I use this to solve Q1?

I'm sorry for being unclear on Q2, as I am also unclear as to what the question is asking. All I know is - two people are playing throw and catch with a ball for sometime (no time given, no velocity given). Would the distance between these two players, increase, decrease, or remain the same. I'm still confused:-(
 
Renue said:
wherever the gap was same
Same as what? Do you mean when the gap is at a minimum or maximum?
Renue said:
rolling on an inclined surface
This is possibly ambiguous. It might mean down an inclined surface, or it really might be allowing any direction.
Renue said:
When two people throw a ball and catch for a period of time, will the distance between them increase, decrease, or remain the same?
Is that the exact wording? Is it a translation?
Renue said:
Speed does not have direction (scalar) and velocity is a vector quantity. How do I use this to solve Q1?
it changes the requirement. If the velocity is to be the same then both the speed and direction (in three dimensions) must be the same.
 
Last edited:
Renue said:
Q2. When two people throw a ball and catch for a period of time, will the distance between them increase, decrease, or remain the same?
I cannot see how this is a scientific question in the absence of any other information.
 
Renue said:
When two people throw a ball and catch for a period of time, will the distance between them increase, decrease, or remain the same?
Here's a guess: someone forgot to mention that they are standing on frictionless ice, perhaps?
 
Question 2 is a bit vague as it depends on whether static friction is present.

However, if friction is not present then try to think about the change experienced by the persons when catching the ball as well as throwing the ball.
 
Kaura said:
However, if friction is not present then try to think about the change experienced by the persons when catching the ball as well as throwing the ball.
Even if friction is not present it is a vague question - it does not give you the initial condition nor any qualifier for what "some time" means.
 

Similar threads

  • · Replies 13 ·
Replies
13
Views
1K
  • · Replies 12 ·
Replies
12
Views
2K
  • · Replies 10 ·
Replies
10
Views
3K
  • · Replies 19 ·
Replies
19
Views
3K
Replies
14
Views
3K
  • · Replies 2 ·
Replies
2
Views
3K
Replies
5
Views
2K
Replies
2
Views
2K
  • · Replies 9 ·
Replies
9
Views
2K
Replies
9
Views
5K