The Student Room Group

Official M4 Edexcel Thread – Wednesday 15th June 2016

Scroll to see replies

Reply 20
Original post by ChuckNorriss
guys, chapter 3 example 2b, that's fp3 right? what else do i need from fp3 for m4? I aint doing fp3...


Look in the formula booklet under FP3! :biggrin:

The only other thing I can think of is resolving vectors (2D collisions with lines at angles).
Original post by ombtom
Look in the formula booklet under FP3! :biggrin:

The only other thing I can think of is resolving vectors (2D collisions with lines at angles).


Just checked the spec, we only gotta know that the from the example shown.
https://qualifications.pearson.com/content/dam/pdf/A%20Level/Mathematics/2013/Specification%20and%20sample%20assessments/UA035243_GCE_Lin_Maths_Issue_3.pdf pg 73.

btw would anyone know if there is a solution bank for the old m4 book? and where can i find it?
thanks
Original post by ChuckNorriss
Just checked the spec, we only gotta know that the from the example shown.
https://qualifications.pearson.com/content/dam/pdf/A%20Level/Mathematics/2013/Specification%20and%20sample%20assessments/UA035243_GCE_Lin_Maths_Issue_3.pdf pg 73.

btw would anyone know if there is a solution bank for the old m4 book? and where can i find it?
thanks


There isnt one and the old book is riddled with mistakes so good luck!


Posted from TSR Mobile
Has anyone done Q3 on the M4 Mock Paper? I keep getting the negative of what I'm supposed to get in the show that... :confused:

M4 Mock Paper Q3.jpeg
Attachment not found
So pumped for exam. First proper maths exam I have this year!!!
Original post by Cryptokyo
So pumped for exam. First proper maths exam I have this year!!!


I still don't understand Relative Velocity diagrams :lol:
Original post by Euclidean
Has anyone done Q3 on the M4 Mock Paper? I keep getting the negative of what I'm supposed to get in the show that... :confused:

M4 Mock Paper Q3.jpeg
Attachment not found


Your diagram is incorrect as you have assumed that it rebounds backwards but in fact it does not. I believe the equations should look like
x+y=ucos(30)x+y=u\cos(30)
yx=eucos(30)y-x=eu\cos(30)
Due to this assumption the tan function yields the negative version of the answer. The angle theta is 90 degress round from where you have it and measured from the horizontal.
(edited 7 years ago)
Original post by Cryptokyo
Your diagram is incorrect as you have assumed that it rebounds backwards but in fact it does not. I believe the equations should look like
x+y=ucos(30)x+y=u\cos(30)
yx=eucos(30)y-x=eu\cos(30)
Due to this assumption the tan function yields the negative version of the answer.


Couldn't the converse be argued though, that if you assume it doesn't rebound backwards it could?

How do you know for sure it doesn't rebound backwards? :confused:

edit: Also if the angle is greater than 120 degrees which would be the condition for the ball to not rebound backwards, the tangent function would need to be negative as tangent of an angle greater than 120 and less than 180 would be negative which isn't possible with the show that unless e>5/3?
(edited 7 years ago)
Original post by Euclidean
Couldn't the converse be argued though, that if you assume it doesn't rebound backwards it could?

How do you know for sure it doesn't rebound backwards? :confused:

The issue is you have measured the wrong angle primarily. The assumption that it travels backwards is not the most important bit. You have measured theta from the negative direction of the velocity and not the positive end. I will post a diagram.
Diagram.png
Note how theta has been measured. The angle is measured as of the velocity carried on past the collision. So it is easier to assume that it does not rebound.
(edited 7 years ago)
I admit to an appalling diagram XD but it gives a representation right? Please just ask if I have not been clear.
Is everyone doing it this year in Year 13? Am I the only Year 12?
(edited 7 years ago)
Original post by Cryptokyo
Diagram.png
Note how theta has been measured. The angle is measured as of the velocity carried on past the collision. So it is easier to assume that it does not rebound.


Original post by Cryptokyo
I admit to an appalling diagram XD but it gives a representation right? Please just ask if I have not been clear.


Ah thank you very much! I understand now :biggrin:

Original post by Cryptokyo
Is everyone doing it this year in Year 13? Am I the only Year 12?


I'm in Year 13, I think the majority sitting M4 are :tongue:
Original post by ombtom


Has anyone got S1 on the same day too?


I got S1 too! But S1 is very boring!
Starting da M4 papers.
Wish me luck lads.


Posted from TSR Mobile
Original post by physicsmaths
Starting da M4 papers.
Wish me luck lads.


Posted from TSR Mobile


I'm on 2004 atm. Relative motion is still :confused: sometimes but getting there

Good luck
Original post by Cryptokyo
Is everyone doing it this year in Year 13? Am I the only Year 12?


I was going to but college fcuked it up. :frown:
Original post by Marxist
I was going to but college fcuked it up. :frown:


Minor, do it next year you doin AFM?


Posted from TSR Mobile
Original post by physicsmaths
Minor, do it next year you doin AFM?


Posted from TSR Mobile


Yeah fam that's what I'm thinking But still would have preferred this year. :frown:
Original post by Marxist
I was going to but college fcuked it up. :frown:


So you did M3 on 18th of May?

Quick Reply