Incredibly clear and to the point. Just want to check, Do we need to know cosine and sin rule for A-level physics, I don't remember needing to use it since GCSE maths
for q3 and 4 how do you know which way to put the arrows of the components Im aware of tip to tail but for q4 I used resolution and I didnt know which direction to place the arrows, I ended up putting the 7n and the horizontal component in opposite directions to get the right answer. but I am not sure which direction to put them without looking at the answer first
so the direction of the initial vectors determines the direction of the components. e.g. in question 4, the x component of the 7N vector is to the right (say positive) which means that the x component of 5N vector will be to the left. (i.e. negative). I hope this helps! It doesn't matter which side you choose to be positive or negative as long as you are consistent.
Hi, for the tugboat question if the two forces has different magnitudes e.g 8.0kN and 8.2kN would the vertical components still cancel out? And if so why?
Hi! So I was wondering if we could use cosine for the 3rd question, because I am getting a different answer if I use that? Could you please explain why we cannot use cosine for it? Thank you so much for the video!!! Has helped me with this topic a lot!
anytime! Do you mean for finding the angle? I just plugged in cos^(-1) of (6.3/6.6) which is adjacenet over hyp. and got 17.3 degrees which is the same answer up to 2 sig. figs. If you don't mean this part just let me know which time in the video and I will have a look!
@@zhelyo_physics So like I just meant that in the same question, when you are finding magnitude, instead of the vertical and horizontal component, as our forces are already tip-to-tail, can't we draw a diagonal resultant force arrow, and then apply cosine, like √(4^2 + 3^2) - (2 x 4 x 3 x cos(140)), and then find the answer? But thanks a lot for your reply!!!
@@zhelyo_physics I tried finding the resultant force for q. 3 using cosine rifle and angle 140 degrees but I got 11.3 so I am not sure why that is wrong and why I must draw my vector in the way you did to get the correct answer. then used the sine rule to find the angle from x axis and got 16.5 degrees. clearly im wrong but im not exactly sure why this method is wrong. any help would be appreciated thanks a lot
Hello sir! thanks for posting an amazing vid it really helped. I had a quick question. When I was solving one of the vector questions I found in a past paper, I was able to find the magnitude but the mark scheme added +- 0.2 next to the magnitude. I don't understand why they did that and how they got +-0.2. Can you plz explain?
This video finally helped me understand vectors😭now I know which channel I'll be referring to for A Level Physics, thanks!!
Really glad to hear you have sorted vectors! Thanks a lot for your kind comment!
Lol same
sir in q5 how did you choose the direction of resultant force to be upwards
Thank you soo much!!! U are very good at teaching.😊
Anytime! Thanks for the comment!
Hello sir Thank you very much for this video. I was just wondering, for the q2, could we use the triangle of forces and then the cosine rule?
absolutely, you would get the same answer
Incredibly clear and to the point. Just want to check, Do we need to know cosine and sin rule for A-level physics, I don't remember needing to use it since GCSE maths
Thanks a lot for the comment! In most exam boards they are given in the formula booklet but you need to check with yours. Good luck!
@ZPhysics hi sir, do we have to use the sin and cosine rule for edexcel too?
for q3 and 4 how do you know which way to put the arrows of the components Im aware of tip to tail but for q4 I used resolution and I didnt know which direction to place the arrows, I ended up putting the 7n and the horizontal component in opposite directions to get the right answer. but I am not sure which direction to put them without looking at the answer first
so the direction of the initial vectors determines the direction of the components. e.g. in question 4, the x component of the 7N vector is to the right (say positive) which means that the x component of 5N vector will be to the left. (i.e. negative). I hope this helps! It doesn't matter which side you choose to be positive or negative as long as you are consistent.
Hi, for the tugboat question if the two forces has different magnitudes e.g 8.0kN and 8.2kN would the vertical components still cancel out? And if so why?
they wouldn't cancel out, as they would have two different components in the vertical direction. Hope this helps!
@@zhelyo_physics Thank you! The video was also really helpful.
Hi! So I was wondering if we could use cosine for the 3rd question, because I am getting a different answer if I use that? Could you please explain why we cannot use cosine for it? Thank you so much for the video!!! Has helped me with this topic a lot!
anytime! Do you mean for finding the angle? I just plugged in cos^(-1) of (6.3/6.6) which is adjacenet over hyp. and got 17.3 degrees which is the same answer up to 2 sig. figs. If you don't mean this part just let me know which time in the video and I will have a look!
@@zhelyo_physics So like I just meant that in the same question, when you are finding magnitude, instead of the vertical and horizontal component, as our forces are already tip-to-tail, can't we draw a diagonal resultant force arrow, and then apply cosine, like √(4^2 + 3^2) - (2 x 4 x 3 x cos(140)), and then find the answer? But thanks a lot for your reply!!!
@@meheresohail1273 You can do it this way too. When you calculate that you get about 6.6 N which is what I got in the video too for the resultant.
@@zhelyo_physics Ohhkkk alright, thank you so much for your time!!
@@zhelyo_physics I tried finding the resultant force for q. 3 using cosine rifle and angle 140 degrees but I got 11.3 so I am not sure why that is wrong and why I must draw my vector in the way you did to get the correct answer. then used the sine rule to find the angle from x axis and got 16.5 degrees. clearly im wrong but im not exactly sure why this method is wrong. any help would be appreciated thanks a lot
Really helped. Thanks so much!
anytime! thanks for the comment!
i love youu
why for question 5 in the vector diagram why dont you draw the arrow from weight tail to the tip of the T
Hi, in vector triangles there are often different correct ways of drawing it, as long as you follow the basic rules.
Is this for cie students too?
absolutely and for anyone who studies physics.
8:15 sir why there is not 20cos38?could you please explain me
because we are looking at the opposite component which in this case is the vertical i.e. 20sin38. Hope this helps!
Hello sir! thanks for posting an amazing vid it really helped. I had a quick question. When I was solving one of the vector questions I found in a past paper, I was able to find the magnitude but the mark scheme added +- 0.2 next to the magnitude. I don't understand why they did that and how they got +-0.2. Can you plz explain?
Anytime! Impossible to say without looking at the question but looking at the +- probably an uncertainty
@@zhelyo_physics oh so do you have to find the uncertainty for every vector question?
which site do u use to show us these
I just use the free Microsoft Whiteboard Software
Sorry sir why didn't you resolve Q4
Showcasing that you can solve the questions with various different techniques.
@@zhelyo_physics i tried to resolve but i failed
hhyolllllllllllllllllllllllllllll
thank you for your help really appreciate you man!!!!!
thanks a lot for your comment, really means a lot!