Predicting the Trajectory of a Thrown Ball on a Moving Train

  • Thread starter shehri
  • Start date
  • Tags
    Ball Fall
In summary: Oh, I agree with that, but I think it's something that the question writer assumed without any thought. :)This is intro physics.
  • #1
shehri
30
0

Homework Statement


If a person is sitting in a train which's starting from rest & he throws a ball upward,then where'll the ball fall?
1)At the position where it's thrown?
2)Behind the person?
or
3) Ahead him?
Thanks.

Homework Equations



Nill.


The Attempt at a Solution



May be theory of relativity is involed,but not sure.
 
Physics news on Phys.org
  • #2
All it involves are Newton's laws of motion.
 
  • #3
Is the train accelerating at the moment when the ball is thrown ? Or in a state of steady motion ?
 
  • #4
The train is accelerating while the ball's thrown.Thanks for interest.
 
  • #5
shehri said:
The train is accelerating while the ball's thrown.
What are the forces that act on the ball, along the horizontal direction, after it is thrown? (I suppose you can neglect any air-friction)
 
  • #6
neutrino said:
What are the forces that act on the ball, along the horizontal direction, after it is thrown? (I suppose you can neglect any air-friction)

No- I don't think you should neglect air-friction. It changes the choice from the list of possible answers.

(Edit) Oh- I see the train is accelerating.

(Of course, 'at the position where it's thrown' is meaningless under even gallilean relativity.)
 
Last edited:
  • #7
christianjb said:
No- I don't think you should neglect air-friction. It changes the choice from the list of possible answers.
C'mon...this is most probably a question from intro-physics/mechanics; air-friction can always be neglected. :wink:
 
  • #8
If the train accelerating when the ball is tossed, the ball will cease to accelerate when it leaves the throwers hand. The thrower will therefore move relative to the ball. All you need now is the direction.
 
  • #9
Air resistance can be neglected in intro to physics and some parts of mechanics courses.

As far as relevancy to your question, the ball will move forward at whatever the velocity of the train is as it is accelerating. :zzz:


You also need to understand, once he let go of the ball from his hand, it is no longer a part of the train so it is in a different dimension whilst the train is still accelerating.

-James
 
  • #10
Is he on one of the seats facing forward? Or one of the seats facing backward? Last train I was on, the seats were arranged that way - facing each other.
 
  • #11
drpizza said:
Is he on one of the seats facing forward? Or one of the seats facing backward? Last train I was on, the seats were arranged that way - facing each other.

Considering the phrasing of answers b and c 'behind him' vs. 'ahead of him', I would bet money that he's sitting in a forward-facing seat.
 
  • #12
DaveC426913 said:
Considering the phrasing of answers b and c 'behind him' vs. 'ahead of him', I would bet money that he's sitting in a forward-facing seat.

Oh, I agree with that, but I think it's something that the question writer assumed without any thought. :)
 
  • #13
This is intro physics. Air has no resistance. Ever.
 

1. Where will the ball fall?

The exact location where the ball will fall is determined by various factors such as the initial velocity, angle of projection, air resistance, and gravitational pull. It is impossible to predict the exact spot where the ball will fall without knowing all of these factors.

2. How can we calculate where the ball will fall?

The trajectory of a falling ball can be calculated using the laws of motion and mathematical equations such as the projectile motion equation. This equation takes into account the initial velocity, angle of projection, and acceleration due to gravity to determine the path of the ball.

3. Can we accurately predict where the ball will fall?

While we can make educated guesses and calculations about where the ball will fall, there are always external factors that can affect the trajectory. For example, wind or air resistance can alter the path of the ball, making it difficult to accurately predict the exact location.

4. Does the weight of the ball affect where it will fall?

The weight of the ball does not directly affect where it will fall. However, it can affect the initial velocity and angle of projection, which can ultimately impact the trajectory and final landing spot of the ball.

5. Is there a way to control where the ball will fall?

There are certain variables that can be controlled, such as the initial velocity and angle of projection, which can influence where the ball will fall. However, there are always external factors that cannot be controlled, making it difficult to have complete control over the final landing spot of the ball.

Similar threads

  • Introductory Physics Homework Help
Replies
1
Views
1K
  • Introductory Physics Homework Help
Replies
7
Views
2K
  • Introductory Physics Homework Help
Replies
7
Views
2K
  • Introductory Physics Homework Help
Replies
5
Views
1K
  • Introductory Physics Homework Help
Replies
7
Views
971
Replies
3
Views
2K
  • Introductory Physics Homework Help
Replies
4
Views
1K
  • Introductory Physics Homework Help
Replies
19
Views
2K
  • Introductory Physics Homework Help
Replies
12
Views
1K
Back
Top