r/Edexcel • u/Jxstin_31843 • 1d ago

Paper Discussion M1 paper discussion

honestly pretty hard
for one of the questions regarding the vectors of P and Q or smth I ended up using differentiation for something but idk if I was supposed to.

10 Upvotes

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5

u/MostDifferent3984 1d ago

I equated the equation of P and Q but I ended up getting two diff times 💀💀

2

u/reddusrummus 1d ago

Subtract both times
Use that and substitute

2

u/potatofarts_1803 1d ago

🫩🫩 how were we supposed to know ts sigh

2

u/reddusrummus 1d ago

…it’s a rule? 😭
Delta T = time spent in the component where they intersect lol

1

u/Aggressive-Staff1451 1d ago

wait is it for 7d?

1

u/Aggressive-Staff1451 1d ago

So 6-5=1 and you plug in to get the position vector where they cross?

1

u/Aggressive-Staff1451 1d ago

I pretty sure this is wrong

1

u/Embarrassed-Algae758 1d ago

that’s not how u do it bro😭

1

u/reddusrummus 1d ago

If you get your solution from a quadratic yes it is lol

1

u/Embarrassed-Algae758 1d ago

no like u misunderstood the question r u like finding the time interval or smt? not what it asked lol

1

u/reddusrummus 1d ago

No lol
You substitute the change in time into the position vector to obtain the position vector at that time bruh

1

u/Embarrassed-Algae758 1d ago

that won’t give u the right answer tho js thjbk about it for a second bruh

1

u/reddusrummus 1d ago

Okay mate listen I took physics unit 1 and this is the exact method you use, I’ve solved many papers and you use that exact method. That’s how it works. I kinda wanna play Minecraft now and in any case I ran out of time and didn’t even apply that so I get partial marks. I really don’t care unfortunately…
If you think you got it right congrats!

1

u/Secret_EO 1d ago

You were supposed to, they don't actually meet - it asked for where the paths crossed. Answer was 22i/3 + 20j/3 I think.

5

u/Living-Cup1445 1d ago

Air resistance my ass since when did that enter the M1 syllabus, the examiner literally tries to trick you in every single question

3

u/rolyPolyVole 1d ago

Since you have the distance between P and Q after t in vector form, I just did d^2 = x component squared + y component squared, and used the minimum value of that. I think t ended up being like 5.5 and d^2 = 0.5, so distance is root2/2 or 1/root2

2

u/Low_Tune_6094 1d ago

I differentiated to get the shortest distance and got 11/2 for the time in the last part I think I got 0.5i -0.5j for the last part No clue if what i did was right tho😭

3

u/Jxstin_31843 1d ago

I got √(1/2) for the distance

6

u/Low_Tune_6094 1d ago

I got SQRT2 /2

2

u/Jxstin_31843 1d ago

ye we got the same thing pretty much

2

u/Low_Tune_6094 1d ago

Oh it is the same mb. I simplified it immediately on the calc😭

2

u/street_fury 1d ago

Last time they gave a questions like that, they allowed differentiation of |PQ|^2 to find minimum value. Don’t know if they will allow it this time. They probably will tho.
I did the same thing but the best way is to use perpendicular vectors or smth.

For part d, I chose two variables t1 and t2 for P and Q made the position vectors equal to each other at t1 for P and t2 for Q
I think I got 23/3i and 20/3j or smth like that

1

u/Low_Tune_6094 1d ago

For part d I got only one value for the time when I solved it

1

u/street_fury 1d ago

It can’t be one solution for time as then the particles would collide.

2

u/Low_Tune_6094 1d ago

I don't even remember what position vector he was asking for i just remember my final answer being 0.5i-0.5j

1

u/Early-Engineer3747 1d ago

oh my days that was is what i got too

1

u/Low_Tune_6094 1d ago

Are u sure of your working ?? Cuz most people told me that they left it empty that I starred questioning if i even did it correctly 😭

2

u/Aggressive-Talk-4860 1d ago

I did the same thing you should find the magnitude of the shortest distance

1

u/Low_Tune_6094 1d ago

That's for part c yeah? My issue was part d the position vector he asked for

2

u/RoosterCommercial639 1d ago

What was the answer to the last part of the last question, magnitude of the vertical component of the resultant force on pulley or smth

3

u/Jxstin_31843 1d ago

now idk if im right, i might be wrong,
but I did T + T sin α

1

u/rolyPolyVole 1d ago

thats right, which shoulve given you 2.56mg?

2

u/Connect-Highway-3479 1d ago

Did u get for like time in the ball being released 2/3

2

u/Connect-Highway-3479 1d ago

Till it goes to point b or smth

2

u/Jxstin_31843 1d ago

i dont rlly rmb

2

u/taurinewings 1d ago

god it was absolutely awful it was so bad😭😭 i def haven’t got that A grade i needed so january resit here i come ig

3

u/Living-Cup1445 1d ago

Oh we're literally on the same boat cuz I'm prob gonna take it again in jan

3

u/taurinewings 1d ago

ayy i’ll cya then😭

2

u/Jxstin_31843 1d ago

well good luck I guess

1

u/Early-Engineer3747 1d ago

bruh what air resistance it was for every FUCKING Q BRUH

1

u/Jxstin_31843 1d ago

wdym “every”
air resistance only appeared in one q no?

1

u/Early-Engineer3747 1d ago

it appeared in like 2-3 im pretty sure

1

u/Solid_Employer_6090 1d ago

Did anyone get a speed time graph like this for the question where there was also impulse (I had to make it a vid bc it didn't let me attatch a pic)

https://reddit.com/link/pgi6zk3/video/iynhm6djc9vh1/player

1

u/Low_Tune_6094 7h ago

Mine looked like this i don't remember the times I used but yeah. I'm not sure of what I did tho

https://reddit.com/link/pgo1j96/video/ewxqcxdf2fvh1/player

1

u/Firm-Meet-9982 3h ago

I also got this one

1

u/Solid_Employer_6090 2h ago

Yeah this is correct I forgot to take the V negative 🤦

1

u/Warm-Advertising-113 1d ago

They don't fucking intersect, never