Question

Playing catch with a friend in a moving train. When you toss the ball in the direction the train is moving, how does the speed of the ball appear to an observer standing at rest outside the train?
I understand basic relative motion, just the ball moving on another moving object confuses me!

Answer 1

Well it would simply appear faster because the speed of the ball and the speed of the train.

Answer 2

Answer:

The speed of the ball appear faster when we observe it from ground frame at rest.

Explanation:

As we know that by relate motion concept

$v_{AB} = v_A - v_B$

here when ball is thrown in the direction of train motion with velocity "v" relative to the train then we will assume here that let say the train at that moment is running at speed $v_T$

now by above concept of relative velocity we will have

$v = v_{ball} - v_T$

now for the speed of ball

$v_{ball} = v + v_T$

so from this equation we can see that the actual speed of ball in ground frame will be more than the speed observed in train frame