12 Nov '08 14:40>
Here is some problems I thought up:
-they are really more of physics problems rather than ones of just logic:
A hummingbird sits at a bottom of an air-tight glass box and you then weigh the box and the hummingbird using some vary sensitive scales.
Then, while you are weighing this box with the hummingbird inside, you see the hummingbird suddenly takes off and starts to hover in the space exactly in the centre of the box so that it is no longer exerting weight down on the bottom of the glass box via its legs -do the scales momentarily show a different reading the moment when the hummingbird takes off but before the hummingbird reaches the centre of the box? -if so, very basically, how does the reading change with time?
-here’s an easier question:
once the hummingbird is hovering in a stationary position relative to the box, is the reading from the scales any different from what it was when the hummingbird was sitting down?
Now you repeat the measurements except this time with the top of the glass box removed so that the box is no longer air-tight. The hummingbird sits at a bottom of this air-tight glass box and you then weigh the box. Then, while you are weighing this box with the hummingbird inside, you see the hummingbird suddenly takes off and starts to hover in the space exactly in the centre of the box so that it is no longer exerting weight down on the bottom of the glass box via its legs. Once the hummingbird is hovering in a stationary position relative to the box, is the reading from the scales any different from what it was when the hummingbird was sitting down?
Now the hummingbird, while it is hovering, very slowly and at a constant speed starts to rise straight upward so that it goes from being at the centre of the box to then being where the lid of the box once was and then to being above and outside the box and continuous upwards until it is a mile above the box -do the reading from the scales change with time and, if so, very basically, how do they change with the hummingbirds position relative to the box?
-they are really more of physics problems rather than ones of just logic:
A hummingbird sits at a bottom of an air-tight glass box and you then weigh the box and the hummingbird using some vary sensitive scales.
Then, while you are weighing this box with the hummingbird inside, you see the hummingbird suddenly takes off and starts to hover in the space exactly in the centre of the box so that it is no longer exerting weight down on the bottom of the glass box via its legs -do the scales momentarily show a different reading the moment when the hummingbird takes off but before the hummingbird reaches the centre of the box? -if so, very basically, how does the reading change with time?
-here’s an easier question:
once the hummingbird is hovering in a stationary position relative to the box, is the reading from the scales any different from what it was when the hummingbird was sitting down?
Now you repeat the measurements except this time with the top of the glass box removed so that the box is no longer air-tight. The hummingbird sits at a bottom of this air-tight glass box and you then weigh the box. Then, while you are weighing this box with the hummingbird inside, you see the hummingbird suddenly takes off and starts to hover in the space exactly in the centre of the box so that it is no longer exerting weight down on the bottom of the glass box via its legs. Once the hummingbird is hovering in a stationary position relative to the box, is the reading from the scales any different from what it was when the hummingbird was sitting down?
Now the hummingbird, while it is hovering, very slowly and at a constant speed starts to rise straight upward so that it goes from being at the centre of the box to then being where the lid of the box once was and then to being above and outside the box and continuous upwards until it is a mile above the box -do the reading from the scales change with time and, if so, very basically, how do they change with the hummingbirds position relative to the box?