Thank you so much for your video,but l am not understanding how we have drag force in water acting downwards, thought there is no drag force but viscosity. Please explain further number 2
First of all , just imagine if an object is moving upwards in the air the direction of air resistance will be downwards ( coz object will push air particles in upwards direction and air particles will push object in downwards ( action and reaction forces ) . In the question , sphere is moving upwards in the water so sphere will push water particles upwards ( action ) and as a reaction particles will push sphere downwards ( reaction ) . Hence , sphere will experience downward force ( drag ) . Air resistance = Drag ( resistive fluid in liquids ) . Hope it helps , feel free to ask if you still have questions .
For Q2 (b), when calculating Fnet why is it roe(w)V(s)g - roe(s)V(s)g? I am confused as earlier it was written that upthrust was roe(w)V(w)g, so why has V(w) changed to V(s) in the Fnet calculation?
Upthrust = roe(w)V(w)g= density of fluid * volume of fluid displaced * g , as in this case sphere is fully submerged so volume of fluid displaced = volume of sphere that's reason V(w)=V(s) . Hope it makes better sense now , let me know if you have any questions .
In the question statement , it's mentioned that initially there is a minimum ( node) at the position of microphone and then as microphone is moved it passes through 3 antinodes ( maxima ) and at the final position of microphone there is also node (minimum ) i.e Initially Node - Antinode -Node -Antinode -Node -Antinode - Node . In short we need to draw a stationary wave which starts at node and ends up at node as well and between first and last node there must be three antinodes . In the video , i have sketched the wave containing 4 nodes and 3 antinodes . Please watch video again , it should be clear to you . Feel free to ask if you still have questions .
sin(theta)= Cos(theta ), if we divide both sides by cos(theta ) then sin(theta)/cos(theta) =1 and sin(theta)/cos(theta) = tan( theta) , Hence , tan(theta) =1 or Theta=arctan(1)=45 degrees . In short , if sin(theta) = Cos( theta ) , then Theta should be equal to 45 degrees . Hope it helps , feel free to ask if you have more questions .
I am assuming you are asking for b(ii) , Original length =1.9980 and total length after extension =2.003 so change in length =2.003-1.9980 =0.005 m .Strain =change in length / original length =0.005/1.9980 =0.0025 =2.5x10^-3 .
Hello again! I’m sorry, I did mean b)ii). But I think my question was, how come for the stress question, the answer is 3.2x10^7 and not 3.2x10^6. Because I’m getting 3.2x10^6 in my calculator when i divide 30 by 9.5x10^-6. I’m sorry if this is a silly question 😅
Speed of stone is not constant so if you want to use t= s/v then v should be average speed and for contant acceleration 'average velocity' =v+u/2 = v/2 .If you use t=36/v/2 =2*36/v =2.70 s
Sir wait... isn't antiparticle of upquark -2/3e?...and antiparticle of downquark is -1/3e...then can antiupquark+antidownquark+antidownquark be a combination?...i meant this on my previous reply... it's hard to write on keyboard
SIR YOU ARE HANDS DOWN THE BEST PHYSICS TEACHER EVER! KEEP UP THIS UNREAL WAY OF TEACHING!!!
This video is amazing. Finally someone who doesn’t just solve but explains too. ❤
logical and crystal, this is by far the best past paper solving video i've ever enjoyed
All the best for today's exams .
3:30 question 1
13:33 question 2
25:20 question 3
38:08 question 4
48:55 question 5
55:32 question 6
58:42 question 7
You are a life saver. Thank you so much for explaining everything indetail
Your videos are the best
Thanks for your comments . It would be much appreciated if you can share channel link in your circle of friends if possible .
@@alevelandapphysics-ali yes sure
@@abhijay8939 appreciated
amazing video, please keep it up!
Thanks, will do! Feel free to ask if you any questions .
Thanks a lot for this! I finally understood upthrust completely and questions related to circuits
Glad it helped!
brilliant content, subscribed
Happy to hear !
Thank you very much for the video, it really helped me a lot
awesome sir
i have my caie
tommarow this will help
All the best for today's exams .
very well explained thankyou sir you earned a subscriber
Thanks for the sub!
Thank you
Thanks for comments . Let me know if you have any questions .
Tq sirr❤
For February /March 2022 Paper 22 , check the following link
ruclips.net/video/HFmnl1jPhgI/видео.html
for question 4b(ii) why didn’t we convert the y gain to Vm^-1
Instead we kept it at Vcm^-1
Amplitude = 2.8 cm *(0.20 V/cm)=0.56 V , cm in the numerator is cancelled with cm in the denominator so no need to convert .
Thank you so much for your video,but l am not understanding how we have drag force in water acting downwards, thought there is no drag force but viscosity. Please explain further number 2
First of all , just imagine if an object is moving upwards in the air the direction of air resistance will be downwards ( coz object will push air particles in upwards direction and air particles will push object in downwards ( action and reaction forces ) . In the question , sphere is moving upwards in the water so sphere will push water particles upwards ( action ) and as a reaction particles will push sphere downwards ( reaction ) . Hence , sphere will experience downward force ( drag ) . Air resistance = Drag ( resistive fluid in liquids ) . Hope it helps , feel free to ask if you still have questions .
For Q2 (b), when calculating Fnet why is it roe(w)V(s)g - roe(s)V(s)g? I am confused as earlier it was written that upthrust was roe(w)V(w)g, so why has V(w) changed to V(s) in the Fnet calculation?
Upthrust = roe(w)V(w)g= density of fluid * volume of fluid displaced * g , as in this case sphere is fully submerged so volume of fluid displaced = volume of sphere that's reason V(w)=V(s) . Hope it makes better sense now , let me know if you have any questions .
31:34 sir we will always divide equation 1 from 2 when we are getting momentum along x and y?
It depends on question but in order to find angle we divide vsin(angle) / vcos(angle ) .
Can you explain that waves amplitude part didn’t get the working also how did you decide where the nodes and antinodes were?
In the question statement , it's mentioned that initially there is a minimum ( node) at the position of microphone and then as microphone is moved it passes through 3 antinodes ( maxima ) and at the final position of microphone there is also node (minimum ) i.e Initially Node - Antinode -Node -Antinode -Node -Antinode - Node . In short we need to draw a stationary wave which starts at node and ends up at node as well and between first and last node there must be three antinodes . In the video , i have sketched the wave containing 4 nodes and 3 antinodes . Please watch video again , it should be clear to you . Feel free to ask if you still have questions .
in q 5 why does the volt metre reads the pd of the heater? i thought volt metres only calculate terminal pd
Voltmeter measures the potential change/differece across any components ( resistor , LDR , thermistor battery,and heater etc) .
how in the Q3 it becomes Tan-1? it was sin theta = cos theta
sin(theta)= Cos(theta ), if we divide both sides by cos(theta ) then sin(theta)/cos(theta) =1 and sin(theta)/cos(theta) = tan( theta) , Hence , tan(theta) =1 or Theta=arctan(1)=45 degrees . In short , if sin(theta) = Cos( theta ) , then Theta should be equal to 45 degrees . Hope it helps , feel free to ask if you have more questions .
hi! for question 6. a)ii) how come it is not 9.5 x 10^-6?
I am assuming you are asking for b(ii) , Original length =1.9980 and total length after extension =2.003 so change in length =2.003-1.9980 =0.005 m .Strain =change in length / original length =0.005/1.9980 =0.0025 =2.5x10^-3 .
Let me know if you still have any questions .
Hello again! I’m sorry, I did mean b)ii). But I think my question was, how come for the stress question, the answer is 3.2x10^7 and not 3.2x10^6. Because I’m getting 3.2x10^6 in my calculator when i divide 30 by 9.5x10^-6. I’m sorry if this is a silly question 😅
Cross-sectional area =0.95 mm^2 =9.5 x10^-7 m^2 . @@caavery
@@alevelandapphysics-ali ohhhhhh okok I understand now. Thank you very much for your help! ☺️
Sir 1 question, if we use the formula v^2=u^2+2as and then use t=s/v we get 1.35 why can’t we get the correct answer that way?
Speed of stone is not constant so if you want to use t= s/v then v should be average speed and for contant acceleration 'average velocity' =v+u/2 = v/2 .If you use t=36/v/2 =2*36/v =2.70 s
@31:49
i a not a maths student but take phy
any other trig eqn's needed to be remembered?
generally sine , cosine and tan are enough .
Hello sir, __
In question 7bi) can it also be ūdd?
Nope coz it has charge =(-2/3e-1/3e-1/3e=-4/3 e . uss can be a possible composition .
Sir wait... isn't antiparticle of upquark -2/3e?...and antiparticle of downquark is -1/3e...then can antiupquark+antidownquark+antidownquark be a combination?...i meant this on my previous reply... it's hard to write on keyboard
It's a possible combination@@farhanshah5966
This paper is quite tough even 41 out of 60 sounds like a big deal to get an A.
It's a good practice and try to improve understanding of challenging concepts .
sir at 36:59 why is it 17² and not (17cos45)²
We are calculating total energy , total energy = Chemical energy = Total KE of all fragments
change ur mic please, the sound is to rusty and loud.
Thanks for pointing out , i'll adjust accordingly .
@@alevelandapphysics-ali thank you for the hard work, also in need of prayers. I got p2 and p5 today :)
All the best for your today's exams . @@wasiqszn9691