You are Here: Home >< Maths

Official M4 Edexcel Thread – Wednesday 15th June 2016

Announcements Posted on
Why bother with a post grad? Are they even worth it? Have your say! 26-10-2016
1. (Original post by Euclidean)
Is this the best method to show that two objects cannot intercept eachother?

Posted from TSR Mobile
A proof by contradiction didn't take too much work
Attached Images

2. A Slice of Pi Euclidean isn't it easiest just to look at the j components only? I mean it's like a 1 line thing which immediately provides a contradiction. Basically Euclideans method but without the need for writing out the full relative velocity expression.
3. (Original post by A Slice of Pi)
A proof by contradiction didn't take too much work
This is a nice method

(Original post by EnglishMuon)
A Slice of Pi Euclidean isn't it easiest just to look at the j components only? I mean it's like a 1 line thing which immediately provides a contradiction. Basically Euclideans method but without the need for writing out the full relative velocity expression.
Probably could have saved myself some time yeah
4. (Original post by Euclidean)
Is this the best method to show that two objects cannot intercept eachother?

I think trying to equate position vectors is a little more complicated, I probably wrote more lines than necessary for this too

Tagging physicsmaths cause I heard he's got sik geometry skills

Tagging A Slice of Pi cause mechanics wizard

Posted from TSR Mobile
Dude. if i was the examiner and ended up marking your paper. i'd give you full marks just for that buffting handwriting. pls explain how you do that.

Posted from TSR Mobile
5. (Original post by ChuckNorriss)
Dude. if i was the examiner and ended up marking your paper. i'd give you full marks just for that buffting handwriting. pls explain how you do that.

Posted from TSR Mobile

It's all intended to distract the examiner from the fact that I don't have a f***in clue what I'm doing
6. Wot.
M4 June 2006, Q6a.
Isnt there an impulse horizontal and vertical in this case? And they are different masses so it must be the case that they are bot unchanged.

Posted from TSR Mobile
7. Nvm Im retarded.

Posted from TSR Mobile
8. (Original post by euclidean)

It's all intended to distract the examiner from the fact that i don't have a f***in clue what i'm doing
looooooooool
9. (Original post by physicsmaths)
Nvm Im retarded.

Posted from TSR Mobile
I think we can all agree this isn't true
10. On Q6 June 2005, the last A mark of part (a) credits an explanation for the range of values of theta. I don't understand why theta has a range of values rather than just one value of arctan(0.75).

Does anyone know why?

Posted from TSR Mobile
Attached Images

11. (Original post by Euclidean)
On Q6 June 2005, the last A mark of part (a) credits an explanation for the range of values of theta. I don't understand why theta has a range of values rather than just one value of arctan(0.75).

Does anyone know why?

Posted from TSR Mobile
that's question 13 from rev ex 1. solution bank should explain it properly. i flopped that question myself tbh.

Posted from TSR Mobile
12. (Original post by Euclidean)
On Q6 June 2005, the last A mark of part (a) credits an explanation for the range of values of theta. I don't understand why theta has a range of values rather than just one value of arctan(0.75).

Does anyone know why?

Posted from TSR Mobile
The question says maximum value is 30km/h. So there is a range of values of Ship A with a corresponding value of theta that will make the two ships intercept. Maybe you have to find an equation of the velocity of A , call it V(A), as a function of theta and find a maximum of theta since we know max velocity of A is 30km/h? I will try and see myself.
13. (Original post by Pyslocke)
The question says maximum value is 30km/h. So there is a range of values of Ship A with a corresponding value of theta that will make the two ships intercept. Maybe you have to find an equation of the velocity of A , call it V(A), as a function of theta and find a maximum of theta since we know max velocity of A is 30km/h? I will try and see myself.
Ah my brain skimmed over this when I read the question!

Thanks
14. (Original post by Euclidean)
On Q6 June 2005, the last A mark of part (a) credits an explanation for the range of values of theta. I don't understand why theta has a range of values rather than just one value of arctan(0.75).

Does anyone know why?

Posted from TSR Mobile
I did this question last week when english muon brought it up. It is on his blog thing since i can't upload it here since i can't find he picture haha.
Basically V<=30 and some manipulation gets the result after sin rule. Now two poistions on either side for intersections.

Posted from TSR Mobile
15. Here it is

Posted from TSR Mobile
16. (Original post by physicsmaths)
I did this question last week when english muon brought it up. It is on his blog thing since i can't upload it here since i can't find he picture haha.
Basically V<=30 and some manipulation gets the result after sin rule. Now two poistions on either side for intersections.

Posted from TSR Mobile
EnglishMuon

Would you mind sharing a link?

I see now, I didn't see how to formulate the inequality. Nice one m8
17. (Original post by physicsmaths)
Here it is

Posted from TSR Mobile
PRSOM
18. (Original post by Euclidean)
Ah my brain skimmed over this when I read the question!

Thanks
I just realized I'm overthinking things again . I guess you just just make two triangles and the second triangle will give -arctan(4/3) where theta is 306.89 degrees due north.
19. (Original post by physicsmaths)
Here it is

Posted from TSR Mobile
Or this
20. (Original post by Euclidean)
EnglishMuon

Would you mind sharing a link?

I see now, I didn't see how to formulate the inequality. Nice one m8
Oh yea basically the thing I missed is that the question says the Maximum speed is .... and I missed that part so I only got the two endpoint values for theta only So since we know its velocity is less than or equal to the value given, the angle can lie anywhere in that range.

Full convo is at the bottom the page http://www.thestudentroom.co.uk/show...3973271&page=8

Register

Thanks for posting! You just need to create an account in order to submit the post
1. this can't be left blank
2. this can't be left blank
3. this can't be left blank

6 characters or longer with both numbers and letters is safer

4. this can't be left empty
1. Oops, you need to agree to our Ts&Cs to register

Updated: July 20, 2016
TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Today on TSR

Who is getting a uni offer this half term?

Find out which unis are hot off the mark here

Brexit: Why you should study law

Poll
Useful resources
Study resources

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.