Discover the Truth About Light Speed: A Lorry Experiment Explained | 1905 Theory

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The discussion centers on a thought experiment involving a moving lorry with two boys, one inside and one outside, observing light from a lamp. When stationary, both boys perceive the light reaching them simultaneously, but when the lorry moves, the boy outside sees the light reach the back of the lorry faster than the front. This discrepancy highlights the principles of Special Relativity, which asserts that no frame of reference is more valid than another when moving at constant speeds. The key takeaway is that while both boys are correct in their observations, their differing perspectives arise from their relative motion. This scenario illustrates the fundamental concept that the speed of light remains constant across all frames of reference.
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help , a hard question!

hi friend , i have a question please help.

there is a lorry with a boy inside it handing a lamp & there is a boy outside the lorry.
When the lorry is in a stationary position both boys notice that the light is reaching to the both sides ( front & back) of the lorry at the same time.
But when the lorry is moving the boy who is inside the lorry notice the same thing , but the boy who is outside the lorry notice that the light is reaching to the back of the lorry faster than reaching to the front.

So , who is right ? & why?

( hint:discovery(theory) or something happened in 1905 is involving )
 
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They are both right, SR says that no frame is more "correct" than any other frame if all frames are moving with a constant speed.
Since the train is moving at a speed relative to the boy outside of the train then the boy outside the train sees events happening at different times when for the boy in the train they happen at the same time. Because the speed of light is the same in all frames, no matter how fast the frames are moving relative to each other.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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