Comparing F(a) and F(n) for a Tennis Ball-Racquet Collision

  • Thread starter Thread starter vysis
  • Start date Start date
  • Tags Tags
    Collision Tennis
Click For Summary

Homework Help Overview

The discussion revolves around the forces involved in the collision between a tennis ball and a racquet, specifically comparing the applied force (F(a)) and the normal force (F(n)). Participants explore the implications of Newton's laws in this context.

Discussion Character

  • Conceptual clarification, Assumption checking, Mixed

Approaches and Questions Raised

  • Participants attempt to clarify the definitions of F(a) and F(n), with some suggesting that both forces are equal due to Newton's third law. Others question the relevance of acceleration in the context of the problem and emphasize the need for a free body diagram (FBD) of the ball.

Discussion Status

The discussion is active, with participants providing insights into the forces at play and referencing Newton's laws. There is a recognition of the complexity of the forces acting on the racquet compared to the ball, and some guidance is offered regarding the drawing of diagrams to better understand the situation.

Contextual Notes

Some participants note the potential confusion around the definitions of forces and the assumptions made regarding the weight of the tennis ball and the anchoring of the racquet by the player's arm.

vysis
Messages
28
Reaction score
0

Homework Statement




for an FDB of an tennis ball hitting the racquet. Is the F(a)=F(n) or is F(a) larger then F(n).



The Attempt at a Solution



I think that F(a) = F(n). According to Newton's second law, they both receive the same force, however since the tennis ball has less mass, it receiver a larger acceleration then the tennis racquet (which is also anchored by the player's arm).

Im pretty sure I am right, but it's always good to be sure.
 
Physics news on Phys.org
vysis said:

Homework Statement




for an FDB of an tennis ball hitting the racquet. Is the F(a)=F(n) or is F(a) larger then F(n).
What do you mean by F(a) and F(n)?

The Attempt at a Solution



I think that F(a) = F(n). According to Newton's second law, they both receive the same force, however since the tennis ball has less mass, it receiver a larger acceleration then the tennis racquet (which is also anchored by the player's arm).
This is not Newton's 2nd law.
Im pretty sure I am right, but it's always good to be sure.
Draw a FBD of the ball, not the racquet. What forces act on the ball? The problem is not asking for acceleration.
 
PhanthomJay said:
What do you mean by F(a) and F(n)?

F(a) = applied force
F(n) = Normal force

This is not Newton's 2nd law.
umm, yea sry. I was typing a bit too quickly. Third and Second law.

Draw a FBD of the ball, not the racquet. What forces act on the ball? The problem is not asking for acceleration.
nono, i mean if a tennis racquet was to hit a tennis ball. Would the applied force and normal force be equal or would applied force be larger?
 
Neglecting the weight of the tennis ball, when the racquet hits the ball, there is only one force acting on the ball...the force of the racquet on the ball, which i guess you are calling an applied force, F(a),which is fine. Now by F(n), I think you mean the force of the ball on the racquet?
 
yea, the equal and opposite force excerted on the racquet stated by the 3rd law.
 
vysis said:
yea, the equal and opposite force excerted on the racquet stated by the 3rd law.
Well, you just answered your question!
 
lol, so to sum it up:

force exerted on ball = force exerted on racquet.
However, ball flies away extremely quickly and racquet doesn't is becaue racquet is heavier and therefore according to Newton's second low, it doesn't accelerate as much (and also since the racquet is anchored to the player's hands)
 
vysis said:
lol, so to sum it up:

force exerted on ball = force exerted on racquet.
Correct! (equal but opposite in direction...force exerted on ball by racquet = force exerted on racquet by ball)
However, ball flies away extremely quickly and racquet doesn't is becaue racquet is heavier and therefore according to Newton's second low, it doesn't accelerate as much (and also since the racquet is anchored to the player's hands)
Sort of. The acceleration of the ball will be in the direction of the average impulse force (which you refer to as the applied force), in accordance with Newton 2. The racquets acceleration (deceleration) is a much more complex phenomenon because of the additional varying force acting on it from the player, and the impulsive nature of the event, but it is still Newton 2 at work.
 
Last edited:
thank you so much
 

Similar threads

  • · Replies 4 ·
Replies
4
Views
5K
  • · Replies 6 ·
Replies
6
Views
8K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 9 ·
Replies
9
Views
4K
  • · Replies 2 ·
Replies
2
Views
5K
  • · Replies 1 ·
Replies
1
Views
6K
  • · Replies 16 ·
Replies
16
Views
7K
Replies
2
Views
2K
  • · Replies 6 ·
Replies
6
Views
4K
Replies
3
Views
20K