There is an error in substitution at 51:07. I substituted 5kg instead of 2kg (the result of being nervous 😬). The correct answer should be 24.5J Please receive my sincerest apologies 🙏🏾
Sir i am a student from Bangladesh And im a so grateful that u have posted these videos in work and energy this really help like,alot i had a lot of confusion amd i really really thank you for clearing it all up Again Thank you sir so much.
Hey sir Thank you so much for pouring out your knowledge and helping us out. Your teachings are so understandable. When I get a distinction for physical science, just know it's because of you. 😊
You're absolutely correct... Perhaps I should put a pinned comment just to acknowledge the error. Thank you for pointing it out... It shows great understanding
Hi sir, in the question with the conserved mechanical energy in the bob, when you took over the 12.25 to the other side, why did you ignore the height on the other side of the equation? should it be height squared when you take it over? and then find the square root of height?
Hey sir. How do we determine on which side fg parallel lies ? Because in the last lesson it was opposing friction but now it is going in the direction of friction.
From Work Energy & Power - Part 1, I realised that Wfg// = Wfg. But fg is a conservative force (1) Is that the reason why Wf// is not included in Wnc=WA + Wfk? (2) Is fg// a non-conservative force since it is equal to fg? Thanks
Wnet works for all circumstances (inclusive of incline surfaces). However, Wnc is particularly helpful in instances where you are given a vertical height or you are required to deternine it.
@@MlungisiNkosi was about to ask the same question but then saw this comment.... This is the best Science and Maths Channel. I thought it is hard to get a distinction in Physical Sciences until I found this page Thank you sir. I'm upgrading my matric and I'm getting that Distinction in Physical Sciences ❤😊
IF YOU'RE DEALING WITH AN INCLINED SURFACE WHEN CALCULATING THE WORK DONE. TO GET THE ANGLE DO U USE THE DIRECTION OF THE DISPLACEMENT OR THE ANGLE CAUSED BY THE INCLINED SURFACE
yess it would , just relax , rest more . study everyday rather ( with a relaxed mind ) the rest will fall into place trust . u will even get distinctions . even if it means that uu have to just watch sir's videos without writing anything down , do it
There is an error in substitution at 51:07. I substituted 5kg instead of 2kg (the result of being nervous 😬). The correct answer should be 24.5J
Please receive my sincerest apologies 🙏🏾
So the lectures also do get nervous 🤗🤸♀️🤸♀️sorry sir 😆
I got the same results "24,50J"
I noticed that
@@thobilemasoka6655 yes they do 😂
you actually did some things wrong like not putting in 1/2 (2) (2^2 - 4.95^2) in the calculator and i got a final answer of -10.7025
6.1.1 24.5 J
6.1.2 h =0.75 m
Wf =10.7 J
Super 👌🏾
Can you please help me out... For my h l got 0.67m... Can you please show me how you got that 0.75m
@@joshuasmbatha2763 that's what I got too
@@joshuasmbatha2763 also got the same answer
Also got 0.67m
Your videos are very helpful please come back and do other topics. You are a good teacher
Thank you and I will definitely keep doing more lessons.
Sir i am a student from Bangladesh
And im a so grateful that u have posted these videos in work and energy this really help like,alot i had a lot of confusion amd i really really thank you for clearing it all up
Again Thank you sir so much.
We welcome you all the way from Bangladesh.... Thank you for being part of the family.
Hey sir
Thank you so much for pouring out your knowledge and helping us out. Your teachings are so understandable. When I get a distinction for physical science, just know it's because of you. 😊
Thanks a million. I'm glad to assist in any way possible
Sir, instead of 61.26 J, aren't you supposed to get 24.50 J?
You're absolutely correct... Perhaps I should put a pinned comment just to acknowledge the error. Thank you for pointing it out... It shows great understanding
Mlungisi deserves a 100 million subscribers
Dankie
Sir on 49:10 you made a mistake,you said 4² instead of 2² and the work done is negative
Thank you for making me aware of it. I sincerely appreciate it… I was thinking of the answer already
trust me to say "let me apply mathematical gymnastics" in my head while calculating tomorrow as I write my physics paper 1 ☺😹🙈
😂😂😂😂😂😂😂😂😂😂😂
Thank you so much Sir. God bless. It was very fruitful.💕
You're most welcome
45:00 why we do not include work done by Fg parallel?
Because it is a conservative force and we only calculating work done by non-conservative forces
Could have not been explained better 🙂
Simplified yet so informative.
May you please do a video on photoelectric effect.
Most definitely... I actually plan to do that as my next topic. I'll finish Stoichiometry and jump straight to it
Very tricky problems there but I blv with more questions I'll be able to understand better thanx a lot for this.
Glad it helped
Hi sir, in the question with the conserved mechanical energy in the bob, when you took over the 12.25 to the other side, why did you ignore the height on the other side of the equation? should it be height squared when you take it over? and then find the square root of height?
I think it would be better to time stamp the question you are referring to...
You made a mistake on the last question
You said 4² instead of 2² on the calculator...so the answer isn't 1.3J it's -10.70J
Thank you for pointing it out Wandile. I guess it does happen even to the best of us.
@@MlungisiNkosi yep
@@wandile2899 thank you for your understanding
Thank you ❤️
I thought I was going astray for sure😅
Please do other topics ,you makes everything clear
I will definitely keep posting... Thank you Fezile.
Hey sir. How do we determine on which side fg parallel lies ? Because in the last lesson it was opposing friction but now it is going in the direction of friction.
It always is down the slope
Very helpful , please keep posting 🙏🏽
I will. Thank you
The lesson was very good.....thanks alot
From Work Energy & Power - Part 1,
I realised that Wfg// = Wfg.
But fg is a conservative force
(1) Is that the reason why Wf// is not included in Wnc=WA + Wfk?
(2) Is fg// a non-conservative force since it is equal to fg?
Thanks
For 1) Yes that’s exactly why. It’s not included .
2) Fg// is a conservative force since it is a component of gravity which is conservative.
some mathematical gymnastics
Lol... Maths can be exactly that at times... Gymnastics 😂
🤣🤣❤
Thank you so much for these videos ❤️ they help a lot 🙏
You're most welcome Amahle... Let's go and fetch those phenomenal results
On last question, So as Wfk is 1.3J , if there was displacement and Fk given , i would get the same answer of 1.3J by using Wfk= Fk×deltaX×Costheta?
Yes you would 😊
Good day sir, maybe i am a bit slow but where did Cos(@) in that formula of P =FxV? I see ∆x/∆t is the average velocity but where did the cos go?
Cos@ is used to convert into horizontal components. @= 0, therefore… Cos0=1 which changes nothing.
My first time understanding this topic...i used to cancel it after receiving a question paper
Am a bit lost there🙆♂️🙆♂️
On the free body diagram
Isn't there supposed to be tension in the direction of the force applied ??😬😬🤧🤧
Nope. Please go to the full lesson
Sir what's the difference between constant velocity and constant speed? do the both mean a=0 ???
Yes both mean the same thing but speed doesn’t include direction where velocity does
Sir does it matter if your Fg|| is on the left or on the right?
Siyabonga sir👍👍
Wamukelekile...
When working with non conservative how do I know whether to use Wnet= change in ek or Wnc=change in Ek +change in Ep
Wnet works for all circumstances (inclusive of incline surfaces). However, Wnc is particularly helpful in instances where you are given a vertical height or you are required to deternine it.
@@MlungisiNkosi thank you
@@MlungisiNkosi was about to ask the same question but then saw this comment.... This is the best Science and Maths Channel. I thought it is hard to get a distinction in Physical Sciences until I found this page Thank you sir. I'm upgrading my matric and I'm getting that Distinction in Physical Sciences ❤😊
Sir how come we got a positive answer for friction
Good afternoon sir
can you please explain why you added the mechanical energy of the block to the mechanical energy of the bob to find the height?
Please provide time stamp
39:12
In calculating the Height h...after collision Ek of Block is 24.50 then Ep of Block is 0.????
Yes… Is that confusing?
sir on the last question why work done by Friction is not negative ??
You're right. We should have had a negative answer
Quality. Thanks
Thank you so much...
Who else found a negative number on the question asked at 46:30 ?
Parallel component of Fg is mg sin theta
Absolutely correct... 😊
Sir I don't understand why you are saying that P =FV what about the cosø and why not P=FVCosø
You may include it
IF YOU'RE DEALING WITH AN INCLINED SURFACE WHEN CALCULATING THE WORK DONE.
TO GET THE ANGLE DO U USE THE DIRECTION OF THE DISPLACEMENT OR THE ANGLE CAUSED BY THE INCLINED SURFACE
Thank you very much mr
You are most welcome
Sir work done by fk is -10.7
Thank you 😊
Thank you Sir👏
Kubonge mina Asanda
🤌🏾🤌🏾your videos are the best
You’re welcome ☺️
Sir when you get to P=Fv what happens to the cos theta
First, it depends on the direction of the force. If it is elevated, the we have to resolve to its horizontal component if it was moving horizontally.
@@MlungisiNkosi alright thank you so much sir
Sir, can u plz tell me where u took this question from, the fist question, the pully
Pulley
@@onickablossom5894 I think it’s from Gauteng Prelim. I don’t remember which year though
Would it be wrong to kill myself over physics 🤔?
Hhayi bo… Why?
yess it would , just relax , rest more . study everyday rather ( with a relaxed mind ) the rest will fall into place trust . u will even get distinctions . even if it means that uu have to just watch sir's videos without writing anything down , do it
Guys is it just me or Mr made some mistakes in this video?
I saw the mistakes too
Yess
Yeah i saw
Yes the kinetic energy part
I'm glad that you were able to pick it up... I guess it does happen to the best of us. Thank you for pointing it out.
Can you please double check your kinetic energy because I got 24.5J.
I made a mistake in substitution...
Don't you hold zoom classes?😭or have a WhatsApp group chat nyana?
I do. Hit me up via email at info@mlungisinkosi.co.za
the mass of the block is 2 not 5 sir .
wenze imistake ... i think🤔
but kengok im confused coz my height is also the same as yours but you used 5kg instead of 2kg .🤔
It really was a mistake in substitution
Thank you 🔥🔥
You're welcome
Could you do the topic , doppler effect
Please follow the link below... You'll thank me later.
ua-cam.com/video/eXTEtbsPfn0/v-deo.html
@@MlungisiNkosi thank you
Thank you so much
You’re welcome
Thank you Sir
My pleasure 🙏🏾
Guys i thought my calculator was broken when i got 24,5J😂😂😂😂