- #1
Figaro
- 103
- 7
In the book I'm reading, there is a discussion about how a person inside a "box" falling in a gravitation field would see himself as compared to someone on the ground. It is as follows
"While the guy is asleep, put him in a spacious box elaborately furnished inside to look exactly like his living
room. We then drop the box from a high-flying airplane. When our friend wakes up, he thinks that he is in his living room. Curiously, though, he feels that he is floating. To an observer on the ground, our friend and his living room are hurtling toward a crunching rendezvous with the ground. Our friend, however, is blissfully unaware of the impending disaster. Since he is accelerating downward at the same rate as the box and all the objects contained inside, he feels that he is not moving downward at all relative to his surroundings. A slight spring in his step and he finds himself drifting toward the ceiling. He feels that he is floating. But this action is interpreted by the ground observer quite differently: our friend, by stepping on the floor, has at the same time decreased slightly his downward velocity and increased slightly the box’s downward velocity. He thinks he is floating upward but in reality his downward plunge is accelerating at the same rate as before."
My questions here are:
1) Where is the floor and ceiling according to the image? It seems unclear as to where it is although given the position of the window, the ceiling should be the top face.
2) My confusion is somehow originating from question 1, if the floor is on the "side" say, left face of the room (since his feet is on that face although it's weird to have a ceiling with windows), by stepping on that face, the outside observer would view him having a horizontal velocity, but horizontal velocity doesn't affect the downward acceleration. So I think what he had done was that he stepped on the bottom face (with the carpet?) and having upward velocity, but this motion was perceived by the ground observer as the guy decreasing his downward velocity and the box gaining downward velocity.
3) What is the statement "accelerating at the same rate as before" pertaining? If he stepped on the floor, he gained upward velocity so the acceleration should decrease right? Or is it the gravitational acceleration in which regardless of what you are doing, it is pulling you at the same rate?
"While the guy is asleep, put him in a spacious box elaborately furnished inside to look exactly like his living
room. We then drop the box from a high-flying airplane. When our friend wakes up, he thinks that he is in his living room. Curiously, though, he feels that he is floating. To an observer on the ground, our friend and his living room are hurtling toward a crunching rendezvous with the ground. Our friend, however, is blissfully unaware of the impending disaster. Since he is accelerating downward at the same rate as the box and all the objects contained inside, he feels that he is not moving downward at all relative to his surroundings. A slight spring in his step and he finds himself drifting toward the ceiling. He feels that he is floating. But this action is interpreted by the ground observer quite differently: our friend, by stepping on the floor, has at the same time decreased slightly his downward velocity and increased slightly the box’s downward velocity. He thinks he is floating upward but in reality his downward plunge is accelerating at the same rate as before."
My questions here are:
1) Where is the floor and ceiling according to the image? It seems unclear as to where it is although given the position of the window, the ceiling should be the top face.
2) My confusion is somehow originating from question 1, if the floor is on the "side" say, left face of the room (since his feet is on that face although it's weird to have a ceiling with windows), by stepping on that face, the outside observer would view him having a horizontal velocity, but horizontal velocity doesn't affect the downward acceleration. So I think what he had done was that he stepped on the bottom face (with the carpet?) and having upward velocity, but this motion was perceived by the ground observer as the guy decreasing his downward velocity and the box gaining downward velocity.
3) What is the statement "accelerating at the same rate as before" pertaining? If he stepped on the floor, he gained upward velocity so the acceleration should decrease right? Or is it the gravitational acceleration in which regardless of what you are doing, it is pulling you at the same rate?