Join our MCAT Study Group: groups/2277468099106607 Check out more MCAT lectures and prep materials on our website: premedhqdime.com Instructor: Dave Carlson
I had a question. So I tried solving this question using your logic: "In one trial, the machine moves towards the patient with a constant speed v. While this is occurring, which description is correct?" And the answer was that frequency remained constant and volume gets louder. I chose the answer where frequency gets higher. Is the question pack incorrect? It's explanation was, "the speed of machine is constant, so doppler shift is constant and frequency is constant and only intensity increases as displacement decreases"
Just so you know, V(relative)/c is talking about electromagnetic waves not sound waves since 'c' is the constant for the speed of light. Using 'c' as the speed of your oscillator (the moving wave, whether that be light or sound) doesn't change anything though.
Truly remarkable that someone can be allowed to get something so WRONG when it's old physics. And TRAGIC - a dozen comments here are saying 'thank you' for being given the wrong information. The speed of a sound wave does NOT change when the source is moving. Frequency/Wavelength changes - yes; but velocity - NO! IF the entire medium (the air) was moving then yes, but that's not being described here. Or if the observer (the person hearing) was moving (i.e., moving through the medium - the air) then that would alter the relative speed of the sound to the observer. Truly appalling to see some pseudo-academic imposter masquerading as an expert and feeding you total garbage. And a lesson to everyone below, "don't trust arbitrary crap just because it's conveniently available on UA-cam".
I was thinking the same thing. My teacher told me this exact thing that speed of source doesn't add up to speed of sound. It only adds up if the whole medium is moving, as in case of a wind. I was going to send this video to him to clarify this thing but found your comment.
This is meant to help us answer MCAT questions....applying it appropriately to questions is paramount...people don't come to here to become physicists. Your point is understood, however the instructor knows his audience.
He never said that speed would change. He is talking about the relative speed of the source and the receiver. Remarkably, some people allow themselves to devalue something without fully understanding it. The formula he is using is a decent approximation depending on the application.
thank you so much for making this! this was EXTREMELY helpful!
God bless your brain cells for making this topic so easy and accessible!! I love your videos. They just make SOOO MUCH SENSE!
A million times better explanation than Khan Academy, thank you so much!!
You're welcome!
Very helpful, simple, Thanks for the time to do this .
I wonder why you don't upload anymore, you're awesome at teaching
Sadly, he got a brain tumor. Search it on google.
www.reddit.com/r/premed/comments/9dblw4/remember_the_premedhq_guy_hes_a_medstudent_at/
Thank you! Our instructor is doing better now. Be sure to Subscribe, as we are planning to begin video production in the near future :)
@remedHQ it's been 8 years ,when are you coming back😢😢😢
God bless bro. Thank you for all these videos and praying for you
He just make this topic easy as a pie. I struggled with this for like months
This is the best EVER .....
This guy is absolutely amazing, his teaching is some next level shit
awesome video. thank you!
Amazing video. Great explanation.
Helpful God bless teacher
Great explanations!
Dave how is your recovery? I hope all is well with you good sir. Thanks as always for your help on difficult topics.
Thank you for your concern! Dave is recovering well, and he is now a medical doctor :)
@@PremedHQ ya love to see it. Congrats to Dave Carlson MD
Thank you!
Excellent 👏
Amazing
I had a question. So I tried solving this question using your logic: "In one trial, the machine moves towards the patient with a constant speed v. While this is occurring, which description is correct?" And the answer was that frequency remained constant and volume gets louder. I chose the answer where frequency gets higher. Is the question pack incorrect? It's explanation was, "the speed of machine is constant, so doppler shift is constant and frequency is constant and only intensity increases as displacement decreases"
Isn’t it different whether the source is moving or the receiver is moving ? And not just their relative speed.
How did you get 35m/s relative velocity if they are moving towards each other? Isn't the vector addition equal to 25m/s of their velocities?
Just so you know, V(relative)/c is talking about electromagnetic waves not sound waves since 'c' is the constant for the speed of light. Using 'c' as the speed of your oscillator (the moving wave, whether that be light or sound) doesn't change anything though.
uhhh.. the dislike must got rejected by med schools...
Truly remarkable that someone can be allowed to get something so WRONG when it's old physics.
And TRAGIC - a dozen comments here are saying 'thank you' for being given the wrong information.
The speed of a sound wave does NOT change when the source is moving.
Frequency/Wavelength changes - yes; but velocity - NO!
IF the entire medium (the air) was moving then yes, but that's not being described here. Or if the observer (the person hearing) was moving (i.e., moving through the medium - the air) then that would alter the relative speed of the sound to the observer.
Truly appalling to see some pseudo-academic imposter masquerading as an expert and feeding you total garbage.
And a lesson to everyone below, "don't trust arbitrary crap just because it's conveniently available on UA-cam".
I was thinking the same thing. My teacher told me this exact thing that speed of source doesn't add up to speed of sound. It only adds up if the whole medium is moving, as in case of a wind. I was going to send this video to him to clarify this thing but found your comment.
This is meant to help us answer MCAT questions....applying it appropriately to questions is paramount...people don't come to here to become physicists. Your point is understood, however the instructor knows his audience.
He never said that speed would change. He is talking about the relative speed of the source and the receiver. Remarkably, some people allow themselves to devalue something without fully understanding it. The formula he is using is a decent approximation depending on the application.