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AQA MM1B - Mechanics 1 -Tuesday 21st June 2016

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so did anyone else get 4 killometers for question 8? i got my mechanics teacher to check it and he said it was right. glad i got that one in the bag, easiest 10 marks in my life. dam the momentum question, who knew a ball could weigh 4 tonnes. feel sorry for people who got 106m for question 8, people forgot to square it. luckily i got my teacher to check this too, what a legend.

Hah

Reply 301

Dynamic_Vicz

Original post by imstitch

I did it exactly the same, but my answer came out to the 168N. I think I've pressed my calculator wrongly :frown:

How many marks will I drop? :frown:

(((

Posted from TSR Mobile

Same I got 164N TO 3SF (around your answer) ... ffs this damn calculator doesn't do its job :frown:

Reply 302

james-parker1997

Original post by TheLifelessRobot

Ano123 posted the numbers. Here it is:
A has an initial velocity 8i+4j and acceleration -0.2i+0.1j, started at origin.
B has an initial velocity 6i+9j and acceleration 0.2i-0.1j and started at position vector 40i+50j.
Find the distance between A and B when their velocities are parallel.

U legend i was trying to find this for a long time.

Reply 303

Sam Webb

Original post by Timotheus

I got T = 12 for the 10 marker but around ~ 46.5 for the final distance

I also got T=12 but I subbed it into my position equations and did pythagoras between i and j differences to get about 105m

Reply 304

Sam Webb

Original post by reuel

Question 7 well most of it

You can't do 16/1.7 because 1.7 was the time taken for the ball to hit the front edge, you had to rework out the time taken to be 1.9 as it would take longer to go further then do 16/1.9 etc

Reply 305

Ano123

Original post by james-parker1997

U legend i was trying to find this for a long time.

Ayy, I'm the legend.
And I know I am.

Reply 306

james-parker1997

Original post by jtebbbs

Worked answers to ramp and football questions:

Attachment not found

Hi can u tell me how were the marks allocated for question 7 for parts A b and C

Reply 307

AaronKhan87

Can someone post the solution to question 1 of the paper please

Reply 308

Khalidak

Original post by littleover13

I hope you are joking... If not you are weak at math

Reply 309

DTAHSFYJFF

Original post by AaronKhan87

Can someone post the solution to question 1 of the paper please

Part A=

momentum before collision= momentum after collision
therefore:
(3x6)-(2x8) = 5v (since the move together as 1 particle we can add their mass together)
therefore V=0.4 ms-1

Part B= (5x0.4)=(5+mass)x0.1
therefore mass of the stationary particle= 15kg

hope that helps :biggrin:

Reply 310

TacticalSushi49

4km? I doubt it it's supposed to be an air display.

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Reply 311

Eisobdxhsonw

For all those people crying about the last question, I too got it wrong as I used T=25 instead of T=5, but one thing it said in the question was that they are both on the SAME horizontal plane throughout their motion(same vertical distance apart), so if you're working out when they're parallel you don't have to piss around with all that gradient **** that you learn in C4, you simply have to work out when the vertical components for velocity are equal to one another (when t=5) and sub T=5 into your distance equation for both plane A and B and take them away from one another to get the distance between them, I might be wrong but the big misconception is that people failed to realise it stated that the planes stayed on their horizontal planes through

This is what I did

Original post by Sam Webb

This is what I did

Thats a really nice layout u got there. too bad i had no clue what to do in the exam :/

Reply 314

CemG

Original post by Eisobdxhsonw

you know, t wasn't 5..

Reply 315

OturuDansay

Original post by Chickenslayer69

Lower. About 53/54 if not lower. I found June 14 the same or easier in comparison.

Yeah me too actually, June 2014 was like 53 and that wasn't too challenging compared to a couple today

Reply 316

Avanpal

Hey guys, for the airplane question, I made an error and got the wrong value of wind speed in part 1. However I got the rest of the questions right (in terms of method), but will I get the error carried forward? It was 2 marks for the first question. For the last question, if I got the wrong value of T, but made the correct substitutions into R equations and correctly calculated displacement (again in terms of method), how many marks can I lose, providing working out is all there. Thanks in advanced.

Reply 317

Sam Webb

The reason the football has to be modeled as a particle is not because of air resistance. This is because in the question they already tell you there's no air resistance, so whether or not the ball is a particle would therefore not cause air resistance.

I think the reason is because if the ball had size you would have to factor in the radius of the ball because the ball's edge would hit the box before the centre of mass arrived.
On top of this if the ball had size it it could rotate, this would have a gyroscopic effect and may affect the trajectory of its path.
If the ball had size there would be multiple answers for how long it takes the ball to hit the rim, because either side of the ball hitting the rim would give multiple answers.