I can not thank you enough as I used your revision videos and I ended up getting an A in gcse physics. Thank you so so very much.Thank you. Youve earned yourself a subscriber
You are so good at teaching and explaining everything, and make it funny too! I now feel a lot more secure about getting the grade i need in physics, thank you!
Thanks. There are already videos on this subject in my A level Revision playlist. But I shall be making some videos on atomic and nuclear physics which fit with the GCSE syllabus a little later.
Namaste! I applaud you for your by far statement, he certainly is the greatest physic's Teacher I have the fortune of being in contact with his youtube video's. May the Fate's bestow all auspiciousness upon him. Infinite bravo's to Him.
This man is great ,and he's physics videos are great for self learning about theoretical as well as practical guide to understanding how are universe is. . . . Sincerely Larry Hernandez . THANKS
It depends on what you mean by fluid mechanics. Fluid statics and bernoulli equation is pretty simple to derive and understand without having much knowledge in math. The navier stokes equations, in the other hand, is know for being difficult, unles you have a solid understanding in mats
Hi sir, hope your fine just wanted to say that your videos are literally the BEST!!!! Very helpful for my CIE (O Level) exam. THANK YOU VERY MUCH SIR!!!
+DrPhysicsA Sir. may I ask what should I need to watch first the A Level or the GCSE revision series? BTW, I just wanna say thank you. You're the best mentor.
Its Newtons formula for the gravitational force between any two masses. The forces fall as the square of the distance. However Potential Energy has only an r term in the denominator.
At approx 9 minutes into the video you talk about "molecular force" on earth which prevents us being pulled through our floorboards etc. Does this force exist on the moon? As man can float on the moon due to weighing only approximately 1/6 as on earth this would also suggest there is no opposing force to balance and thus prevent being able to float
A certain force applied to a body A gives it an acceleration of 10 ms-2. The same force applied to body B gives it an acceleration of 15 ms-2. If the two bodies are joined together and the same force is applied to the combination, the acceleration will be (1) 6 ms-2 (2) 25 ms-2 (3) 12.5 ms-2 (4) 9 ms-2
Hello Sir, i have this same confusion that why does stuff move if third law is valid. for example i have a book on table and i apply 1N force on it but the book doesn't move now i apply 2N force but the book is still there but if i apply 3N force, the book starts accelerating. That means book is only reacting back with 2N nd the left 1N is accelerating it so isn't it against 3rd law?
Well, for an object to move the force needs to be large enough in relation to the mass of the object and the other forces acting on the object for it to actually move. So, on earth you have gravity and air resistance stopping it from moving from 1 N of force, and you have the mass of the book as well which can cancel out the 1 N force
The "first law"...... gives me trouble sometimes.... for instance If I wave my arm around the room am I being acted on by an external force?? I guess its a chemical force/..
How did they figure out the squared seconds and the squared radius? And is that squared in a geometrical sense, like (a+b)^2 or a^2+b^2=c^2? Sorry if that's a dumb question, but I always wonder how the people writing the equations come by squaring things, and if they are using geometry to justify it.
F=M.a ===> a=F/M ===> F(is Kg.m/s²) | M(is Kg) so if you put on the formula, the "Kg" cancel and you're left with a=m/s² ||| I hope i answered your question, i didn't quite get it.
It's just the amount of time compounding on itself in order to capture the idea of acceleration. IE, a time unit * a time unit. Without that compounding property then it would simply be a static velocity, as in meters/second. So it's easier to just write acceleration as seconds^2 and in maths people do this all the time to clean up redundancy in the expression. Doesn't always mean there is a dimensional basis behind it. Sometimes there could be some obvious basis for it in geometry that follows along with the traditional words "square" and "cube" as they were intuitively intended, other times not so much as in this case. You just need to find how the equation was derived to understand why it really is there (and I would prefer to call it "how they discovered it as truth" rather than implying it was invented or sold by a person). If you desired you could still treat exponents as "dimensions" anyway and plot it out in a graph of that space, and the math behind it remains perfectly intact, albeit a little difficult to interpret if there's more than 1 time dimension or more than 3 spacial ones. If you google "acceleration" and look at the images tab you will see a lot of graphs showing exactly those types of mappings. Ex: bristol.k12.ct.us/page.cfm?p=7080
DrPhysicsA Out of curiosity at 9:56 in the vid the reason also why we wouldn't fall through the floor board due to gravity other than the strength of the board, could it also be because of a normal force that acts opposite to our downward weight force?
snipez285 then why don't you stop immediately if you jump from a higher level to a lower level owing to that "anti" force.... scientist nowadays are trying to introduce an antigravity force caused by antimatter to describe the acclerating expansion of the universe..
Arunava Sarkar that normal force applies only to objects that are stationary. For example If a book is placed on a table there will be a Normal reaction acting upwards to counteract the weight of the book, that normal reaction times the coefficient of friction is the frictional force,but antigravity isn't the normal force thats why you will fall if you jump from a high to low level. (and you are weightless based on general relativity). Indeed antigravity is interesting and is caused by dark matter and its still a great work in progress by Physicists :))
The force that stops you going through the board is electromagnetic force and the strong and weak force, equal and opposite, they are also the things that determine a materials strength
So if there was no resistances to motion, there would only be an initial acceleration, and after that a constant velocity. so would f=ma turn to f=mv or something else? surely it can't remain the same cuz it would make the F 0?
+cjp21211 If there was no resistance (e.g. friction) then F would still equal ma. A body given an initial force would accelerate during the period for which the force applied and would then travel at the velocity reached during the acceleration. A further force would result in further acceleration.
+DrPhysicsA thank you! sorry if it seemed like a silly question. love your videos! spectacular job, really. great pace, filled with information. thanks for the response!
Sorry, it was Newton's laws of motion. You had force vectors pointing in different directions with different magnitudes and you put them tip to tail and calculated I guess net force. Did you have an angle value and use trigonometry?
Patricia Powers OK I see. Yes at 27:21 for example, you would need to know the angle to do the calculation or to draw it graphically. I was simply illustrating the process.
if you draw the forces tip to tail as I have done then the resultant force is the line which goes from the tail of the first to the tip of the second and in that direction.
It largely depends on what you want to learn. My GCSE course has already got videos on Archimedes principle and hydraulics. My A-level course goes a little deeper into this.
I want to learn enough to optimize a rocket engine nozzle and calculate the pressures it will endure. I want to study aerospace engineering but my grades arent really that high (my average is about 7.9), and i dont think i will be able to get into a good university unless i sit for a level physics and math. What other things could i do in order to get into a good unversity?
The full set of videos in this GCSE playlist is at ua-cam.com/play/PLijqQiSMHnP2aEdAajHRDsralGH9n3gHT.html I hope it lists what you need. If not you might also try the A Level list ua-cam.com/play/PL5D99A319E129A5B7.html
By far the best physics teacher on UA-cam!
Exactly dude btw how u doing ? Cuz yr comment was 5 years ago 🤣
😝
8 years have passed......
Sir you explain great. Please come back and continue do videos.
I can not thank you enough as I used your revision videos and I ended up getting an A in gcse physics. Thank you so so very much.Thank you. Youve earned yourself a subscriber
You are so good at teaching and explaining everything, and make it funny too! I now feel a lot more secure about getting the grade i need in physics, thank you!
Thank You for doing this. You are a very good teacher!
Greetings from Germany :)
Seconds into the video, I thought YOU ARE BETTER THAN MY PHYSICS TEACHER PLEASE DO THINGS ON NUCLEAR FISSION AND FUSION, YOU ARE AMAZING!
Thanks. There are already videos on this subject in my A level Revision playlist. But I shall be making some videos on atomic and nuclear physics which fit with the GCSE syllabus a little later.
Very nice, keep the good work
Namaste! I applaud you for your by far statement, he certainly is the greatest physic's Teacher I have the fortune of being in contact with his youtube video's. May the Fate's bestow all auspiciousness upon him. Infinite bravo's to Him.
This man is great ,and he's physics videos are great for self learning about theoretical as well as practical guide to understanding how are universe is. . . . Sincerely Larry Hernandez . THANKS
Best physics video revision I've ever seen.
It depends on what you mean by fluid mechanics. Fluid statics and bernoulli equation is pretty simple to derive and understand without having much knowledge in math. The navier stokes equations, in the other hand, is know for being difficult, unles you have a solid understanding in mats
I like this teacher. He knows his Physics. We are very few teachers who demonstrate these kind of little actions to the students.
Very nice video again, love your videos and your explanation of terminal velocity was just hilarious, job well done!
Would like to leave a thank you as I now understand the topic, which will be a large part of my exam tomorrow. Thank you =)
Wow because of you i am doing my GCSE's at the age of 12! You really make physics understandable.
It would be great if you did one video purely on algebra but I know this isn’t a math channel
it's very useful many thanks "dr"
i like your videos and i wish you make another channel as Dr maths A
Your videos really helped me a lot. Please make a video about Material(Young's Modulus). Please I really need help.
HAHA so cute "hooray!! i remembered the square!" XD💕
Information is easy to understand. Thank you Dr Physics A
PLEASE COME BACK!!
Very clear and straight forward explanations
best physics teacher indeed
Hi sir, hope your fine just wanted to say that your videos are literally the BEST!!!!
Very helpful for my CIE (O Level) exam.
THANK YOU VERY MUCH SIR!!!
+comphys nerd You are welcome. Thanks for saying so. Hope the exam went/goes well.
+DrPhysicsA Sir. may I ask what should I need to watch first the A Level or the GCSE revision series? BTW, I just wanna say thank you. You're the best mentor.
+Vault Von Thanks. GCSE first then A Level.
DrPhysicsA OK, Thanks for replying back. It's a big help to me.
Brilliant, many thanks!
How r u doing I'm asking cuz you're comment was 5 years ago 🤣
Fantastic lectures and superb way of teaching. Thank you for this.
Just a quick question, at 13:38 why r^2 instead of r if I may ask?
Its Newtons formula for the gravitational force between any two masses. The forces fall as the square of the distance. However Potential Energy has only an r term in the denominator.
@@DrPhysicsA thank god you are alive lol
@@DrPhysicsA why don’t you make vids anymore
Thank you, these are great.
thanks you soooo much for this it has really helped me.
At approx 9 minutes into the video you talk about "molecular force" on earth which prevents us being pulled through our floorboards etc. Does this force exist on the moon? As man can float on the moon due to weighing only approximately 1/6 as on earth this would also suggest there is no opposing force to balance and thus prevent being able to float
A certain force applied to a body A gives it an acceleration of 10 ms-2. The same force applied to body B gives
it an acceleration of 15 ms-2. If the two bodies are joined together and the same force is applied to the
combination, the acceleration will be
(1) 6 ms-2 (2) 25 ms-2 (3) 12.5 ms-2 (4) 9 ms-2
Again, thanks soo much!
Hello Sir, i have this same confusion that why does stuff move if third law is valid.
for example i have a book on table and i apply 1N force on it but the book doesn't move now i apply 2N force but the book is still there but if i apply 3N force, the book starts accelerating. That means book is only reacting back with 2N nd the left 1N is accelerating it so isn't it against 3rd law?
Well, for an object to move the force needs to be large enough in relation to the mass of the object and the other forces acting on the object for it to actually move. So, on earth you have gravity and air resistance stopping it from moving from 1 N of force, and you have the mass of the book as well which can cancel out the 1 N force
@@poddopetals finally someone in 2019 🤣🤣🤣😅😅
Excellent!
your video helped me a lot . this is good stuff.
20:05 You say that except air resistance the 600 N backward force is also "friction". What kind of friction?
The "first law"...... gives me trouble sometimes.... for instance If I wave my arm around the room am I being acted on by an external force?? I guess its a chemical force/..
your my hero😍
I think I'm in love 😍
@@danhubbard3844 me too ❤
How did they figure out the squared seconds and the squared radius? And is that squared in a geometrical sense, like (a+b)^2 or a^2+b^2=c^2? Sorry if that's a dumb question, but I always wonder how the people writing the equations come by squaring things, and if they are using geometry to justify it.
F=M.a ===> a=F/M ===> F(is Kg.m/s²) | M(is Kg) so if you put on the formula, the "Kg" cancel and you're left with a=m/s² ||| I hope i answered your question, i didn't quite get it.
SpyFox Orion Thanks for the reply but I was asking about the square units, and why they were in square units. I looked the answer up on google.
It's just the amount of time compounding on itself in order to capture the idea of acceleration. IE, a time unit * a time unit. Without that compounding property then it would simply be a static velocity, as in meters/second. So it's easier to just write acceleration as seconds^2 and in maths people do this all the time to clean up redundancy in the expression. Doesn't always mean there is a dimensional basis behind it. Sometimes there could be some obvious basis for it in geometry that follows along with the traditional words "square" and "cube" as they were intuitively intended, other times not so much as in this case. You just need to find how the equation was derived to understand why it really is there (and I would prefer to call it "how they discovered it as truth" rather than implying it was invented or sold by a person). If you desired you could still treat exponents as "dimensions" anyway and plot it out in a graph of that space, and the math behind it remains perfectly intact, albeit a little difficult to interpret if there's more than 1 time dimension or more than 3 spacial ones. If you google "acceleration" and look at the images tab you will see a lot of graphs showing exactly those types of mappings. Ex: bristol.k12.ct.us/page.cfm?p=7080
I love you, prof!
I liked you're comment and BTW how r u cuz you wrote this comment 5 years ago 🤣
DrPhysicsA Out of curiosity at 9:56 in the vid the reason also why we wouldn't fall through the floor board due to gravity other than the strength of the board, could it also be because of a normal force that acts opposite to our downward weight force?
snipez285 then why don't you stop immediately if you jump from a higher level to a lower level owing to that "anti" force.... scientist nowadays are trying to introduce an antigravity force caused by antimatter to describe the acclerating expansion of the universe..
Arunava Sarkar that normal force applies only to objects that are stationary. For example If a book is placed on a table there will be a Normal reaction acting upwards to counteract the weight of the book, that normal reaction times the coefficient of friction is the frictional force,but antigravity isn't the normal force thats why you will fall if you jump from a high to low level. (and you are weightless based on general relativity). Indeed antigravity is interesting and is caused by dark matter and its still a great work in progress by Physicists :))
The force that stops you going through the board is electromagnetic force and the strong and weak force, equal and opposite, they are also the things that determine a materials strength
Dr,haw expain this: 1kg=1000g vs 9,81n=9,81 m/sec^2
love that British accent
Thank you so much
So if there was no resistances to motion, there would only be an initial acceleration, and after that a constant velocity. so would f=ma turn to f=mv or something else?
surely it can't remain the same cuz it would make the F 0?
+cjp21211 If there was no resistance (e.g. friction) then F would still equal ma. A body given an initial force would accelerate during the period for which the force applied and would then travel at the velocity reached during the acceleration. A further force would result in further acceleration.
+DrPhysicsA
thank you! sorry if it seemed like a silly question.
love your videos! spectacular job, really.
great pace, filled with information. thanks for the response!
I have a general question. How can the tree exert force on us if we provide it a force of push? If we push it, the tree wont push us back..
If there was no force pushing back you would litterally push it away or you’d go through it
"the mass of the earth which is extremely heavy, and yours, which isn't-" well, i disagree XD
Lmao
How did we figure out the third side of the Triangle of Forces without an angle?
Depends where abouts on the video this occurred. But did I use Pythagoras?
Sorry, it was Newton's laws of motion. You had force vectors pointing in different directions with different magnitudes and you put them tip to tail and calculated I guess net force. Did you have an angle value and use trigonometry?
Patricia Powers OK I see. Yes at 27:21 for example, you would need to know the angle to do the calculation or to draw it graphically. I was simply illustrating the process.
At 27:22 how do you know which direction the force is acting in?
if you draw the forces tip to tail as I have done then the resultant force is the line which goes from the tail of the first to the tip of the second and in that direction.
I see ty
29:04 could you use Pythagorean theorem?
You cannot, that is only used if there is right angle triangle here
why R^2 ? could you explain please.
Kansu kan At what time on the video does this arise?
DrPhysicsA I think they're talking about 10:40
+Kansu kan At 10:40 I am just using the full equation from Newton's law of gravitation. F = G m1 m2 / r^2
Do you think it would be impossible for a 15 year old to learn up to fluid mechanics in 1 year?
It largely depends on what you want to learn. My GCSE course has already got videos on Archimedes principle and hydraulics. My A-level course goes a little deeper into this.
I want to learn enough to optimize a rocket engine nozzle and calculate the pressures it will endure. I want to study aerospace engineering but my grades arent really that high (my average is about 7.9), and i dont think i will be able to get into a good university unless i sit for a level physics and math. What other things could i do in order to get into a good unversity?
Mardlamock N Sounds like Physics and Maths are going to be pretty important for what you want to do. Stick at it. All good wishes.
Thanks, im learning calculus on my own and trying to understand more physics as i deepen my mathematical knowledge
I know d = vt but i still like alcohol
thanks indeed Sir. do you have videa on p3 ( unit three ) separate science.
The full set of videos in this GCSE playlist is at ua-cam.com/play/PLijqQiSMHnP2aEdAajHRDsralGH9n3gHT.html I hope it lists what you need. If not you might also try the A Level list ua-cam.com/play/PL5D99A319E129A5B7.html