You don't actually need to transform into C's frame of reference for this problem. From A's frame: u' = (u - v) / (1 - uv/c^2) Let's define terms: v is the speed of C as seen by A. u is the speed of B as seen by A. u' is the speed of B as seen by C. The key thing to note here is that v = u'. This is because A sees C travelling at some velocity, so C sees A travelling at the same velocity but in the opposite direction. Because C sees A and B at the same speeds but opposite directions, then C sees B the same way A sees C. Plugging in that u' = v: v = (u - v) / (1 - uv/c^2) Now we plug in the numbers: v = (0.8c - v) / (1 - 0.8v/c) Doing simple algebra, we find that v = 0.5c
why do you explain so slowly and repeat things so much? More often than not I find myself playing your videos at x2 just so I don't get distracted. Is it possible to work a bit faster when tackling more specialized subjects?
Special relativity is a specialized topic. Probably the only ones who need to know about it are people who focusing in physics related fields. You won't find as many views you would find in an introduction to kinematics/electricity/magnetism video because it is something that's required for not just physics students, but engineers and students from other natural sciences. Once you get passed the 'introductory' (technically this is still an intro to special relativity) courses, the view count will decrease drastically, regardless of the channel.
You are a life saver!
You don't actually need to transform into C's frame of reference for this problem. From A's frame:
u' = (u - v) / (1 - uv/c^2)
Let's define terms:
v is the speed of C as seen by A.
u is the speed of B as seen by A.
u' is the speed of B as seen by C.
The key thing to note here is that v = u'. This is because A sees C travelling at some velocity, so C sees A travelling at the same velocity but in the opposite direction. Because C sees A and B at the same speeds but opposite directions, then C sees B the same way A sees C.
Plugging in that u' = v:
v = (u - v) / (1 - uv/c^2)
Now we plug in the numbers:
v = (0.8c - v) / (1 - 0.8v/c)
Doing simple algebra, we find that v = 0.5c
elastic collision in the laboratory frame of reference
This one is the first video that confused me in the whole of the Relativity series.
why do you explain so slowly and repeat things so much? More often than not I find myself playing your videos at x2 just so I don't get distracted. Is it possible to work a bit faster when tackling more specialized subjects?
Mr. Khan, at the beginning of this video you said A is moving with constant velocity. But didn't say with respect to which frame.
its constant in every frame
but value may differ
for ex if it is 0.8c in a refrence it may be 0.5c in another. but constant in their respective frames
what happened to this channel?
+Hydra Games in what respect?
look at the views and sub count...
+Hydra Games that is unsurprising. Subs accumulate and the channel is old. So most of the sub swill be dead subs.
;_; true... Its a good channel though
Special relativity is a specialized topic. Probably the only ones who need to know about it are people who focusing in physics related fields. You won't find as many views you would find in an introduction to kinematics/electricity/magnetism video because it is something that's required for not just physics students, but engineers and students from other natural sciences. Once you get passed the 'introductory' (technically this is still an intro to special relativity) courses, the view count will decrease drastically, regardless of the channel.
first
3rd llellelllelelelellelel