I often encounter simple stuff I can't understand. Here's one I'd like to cross off my list.
>Train is going 100km/h relative to the ground, a ball is thrown at 100km/h relative to the ground from the opposite direction.
>a) How fast does the conductor of the train percieve the ball to be approaching?
>b) The ball bounces off the train. What velocity does the conductor perceive now?
>c) What about a guy standing on the train station?
The answers, as I understand it, are
>a) 200km/h
>b) 200km/h
>c) 300km/h
But I can intuitively only understand a). My brain says that relative velocity is not a "conserved quantity" so it doesn't make sense for it to be 200 as it bounces back from the train. If it was 200km/h only because it was going in the opposite direction to the train, why would it still be the same when they're headed in the same direction?
>Train is going 100km/h relative to the ground, a ball is thrown at 100km/h relative to the ground from the opposite direction.
>a) How fast does the conductor of the train percieve the ball to be approaching?
>b) The ball bounces off the train. What velocity does the conductor perceive now?
>c) What about a guy standing on the train station?
The answers, as I understand it, are
>a) 200km/h
>b) 200km/h
>c) 300km/h
But I can intuitively only understand a). My brain says that relative velocity is not a "conserved quantity" so it doesn't make sense for it to be 200 as it bounces back from the train. If it was 200km/h only because it was going in the opposite direction to the train, why would it still be the same when they're headed in the same direction?
