x Turn on thread page Beta
 You are Here: Home >< Maths

# AQA AS M1 Mechanics 1 21st June 2016 [Exam Discussion Thread] watch

1. howd u get 12 seconds
Distance I got 106, got t=12 and subbed into the position vectors, found the difference between them and took the modulus of that value
What if u got a different value of T sub it in and do the rest, do u lose rest of the marks
3. (Original post by johnapplebottom)
howd u get 12 seconds
Basically all you had to do is make an equation for the final velocity for each helicopter using v = u + at leaving t the same in both equations.

Then since the velocity is parallel at t the resultant of the velocities will be acting at the same angle to the horizontal so you could say that tan(angle) = J/I for both the velocities. Then since they both equal tan(angle) you can set J/I for both velocities equal to eachother and solve to get t.

Then from this you can find displacement of the two helicopters at time t. Then finding the distance between the two to give 106 m 3.s.f
4. Alright, here's my working out for Q8. I missed out on the last bit where you work out SB and left it as -105.625i -125j in the actual exam, so I won't get full marks for it :/

https://imgur.com/a/qLIc8
5. (Original post by thestickystickma)
Alright, here's my working out for Q8. I missed out on the last bit where you work out SB and left it as -105.625i -125j in the actual exam, so I won't get full marks for it :/

https://imgur.com/a/qLIc8
Thats wrong. First off you cant square a vector so v^2 = u^2 + 2as will produce a false answer
6. (Original post by Crizmikk)
Thats wrong. First off you cant square a vector so v^2 = u^2 + 2as will produce a false answer
Oh ffs
7. (Original post by johnapplebottom)
how did u get 13.2 i got 12.3 lol
You sure you never mixed the numbers around (I got 13.2)? the numbers are similar
8. From the look of things on here, I think I've done quite well
9. It was going so well up until question 7!! And then I just froze and couldn't do 7c at all (doesn't help that I'm not great at projectiles anyway). And then question 8 happened and I just could not even with that...surprise 10 marker and my worst part of mechanics yay...WHY COULD THE 10 MARKER HAVE NOT BEEN ON MOMENTUM?!
10. (Original post by KV848)
It was going so well up until question 7!! And then I just froze and couldn't do 7c at all (doesn't help that I'm not great at projectiles anyway). And then question 8 happened and I just could not even with that...surprise 10 marker and my worst part of mechanics yay...WHY COULD THE 10 MARKER HAVE NOT BEEN ON MOMENTUM?!
Haha I found the question with the angle between the ramp and horizontal hard but q7 and 8 were lightweight, should of expected a 10 or 9 marker on position vectors since they came up last year
11. how should 7)c) be done?
I initially subbed in the time to part a or b put, and worked out 'u' from that. This gave me like 14.1m/s but this didn't seem to make the vertical height right.
So I made the wonderful mistake of a last minute change of my working. The horizontal distance was just +3 to the distance from the previous part, but after the vertical height seemed wrong, I created two simultaneous equations which cancelled out 'u' (what I called the initial velocity), and gave me a time. I then subbed this time into the equation which gave me 6.4 or something, which seems unlikely, as it should surely increase if the ball is to travel 3m more horizontally?? Is either remotely the right method??
12. (Original post by yelash)
how should 7)c) be done?
I initially subbed in the time to part a or b put, and worked out 'u' from that. This gave me like 14.1m/s but this didn't seem to make the vertical height right.
So I made the wonderful mistake of a last minute change of my working. The horizontal distance was just +3 to the distance from the previous part, but after the vertical height seemed wrong, I created two simultaneous equations which cancelled out 'u' (what I called the initial velocity), and gave me a time. I then subbed this time into the equation which gave me 6.4 or something, which seems unlikely, as it should surely increase if the ball is to travel 3m more horizontally?? Is either remotely the right method??
t is would be different in part 7c because its traveled a different distance at a different speed. All you had to do is make an equation for horizontal displacement(16.something + 3) in terms of t and v (the initial velocity) and an equation for the vertical displacement in terms of t and v (the initial velocity). Then from the first equation express v in terms of t and sub into the second equation to get 13.2 m/s
13. (Original post by Crizmikk)
t is would be different in part 7c because its traveled a different distance at a different speed. All you had to do is make an equation for horizontal displacement(16.something + 3) in terms of t and v (the initial velocity) and an equation for the vertical displacement in terms of t and v (the initial velocity). Then from the first equation express v in terms of t and sub into the second equation to get 13.2 m/s
Hmm seems my changed method was right even if my answer wasn't. Might pick up a few method marks hopefully

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:
Updated: June 22, 2016
Today on TSR

### Boyfriend slept with someone else

...we were on a break

### Mum says she'll curse me if I don't go to uni

Poll
Useful resources

Can you help? Study help unanswered threadsStudy Help rules and posting guidelinesLaTex guide for writing equations on TSR

## Groups associated with this forum:

View associated groups

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