Turn on thread page Beta
    • Thread Starter
    Offline

    5
    ReputationRep:
    Hi can someone help me with this M1 question

    "A particle starts from a point O with an initial velocity of 2m/s and travels along a straight line with constant acceleration 2m/s^2. Two seconds later another particle starts from rest at O and travels along the same line with an acceleration of 6m/s^2. Find how far from O the second particle overtakes the first
    Offline

    15
    ReputationRep:
    Are you sure you have the accelerations copied down correctly as if they both have the same acceleration along the same path and Particle 1 has already started accelerating before particle 2 then I don't see how particle 2 would be able to even overtake it at all.
    Offline

    15
    ReputationRep:
    (Original post by Rhiannemahey)
    Hi can someone help me with this M1 question

    "A particle starts from a point O with an initial velocity of 2m/s and travels along a straight line with constant acceleration 2m/s^2. Two seconds later another particle starts from rest at O and travels along the same line with an acceleration of 2m/s^2. Find how far from O the second particle overtakes the first
    What have you tried so far?

    looks like you need to form 2 equations and solve them simultaneously.

    you make initial conditions for each particle

    and the difficult thing here is reasoning with the time. The question you ask and must find out(cus this is the difficult bit) is, is the time for particle 1 t-2? or is it t+2 or is the time for particle 2 t-2 or is it t+2? once you've found that out you should have an easy time.
    • Community Assistant
    • Study Helper
    Offline

    20
    ReputationRep:
    Community Assistant
    Study Helper
    (Original post by Rhiannemahey)
    Hi can someone help me with this M1 question

    "A particle starts from a point O with an initial velocity of 2m/s and travels along a straight line with constant acceleration 2m/s^2. Two seconds later another particle starts from rest at O and travels along the same line with an acceleration of 2m/s^2. Find how far from O the second particle overtakes the first
    Please check that you posted the question correctly.
    • Thread Starter
    Offline

    5
    ReputationRep:
    (Original post by will'o'wisp2)
    What have you tried so far?

    looks like you need to form 2 equations and solve them simultaneously.

    you make initial conditions for each particle

    and the difficult thing here is reasoning with the time. The question you ask and must find out(cus this is the difficult bit) is, is the time for particle 1 t-2? or is it t+2 or is the time for particle 2 t-2 or is it t+2? once you've found that out you should have an easy time.
    I get that for particle 2 the time is t-2 because it is 2 seconds later but how do you start this question?
    Offline

    15
    ReputationRep:
    (Original post by Rhiannemahey)
    I get that for particle 2 the time is t-2 because it is 2 seconds later but how do you start this question?
    done some calculations and i get an answer but are you sure the conditions are right?

    If the acceleration of p1=p2 but the initial velocity of p1 is 2 and p2 is at rest, how can p2 ever overtake p1?
    • Thread Starter
    Offline

    5
    ReputationRep:
    (Original post by S.H.Rahman)
    Are you sure you have the accelerations copied down correctly as if they both have the same acceleration along the same path and Particle 1 has already started accelerating before particle 2 then I don't see how particle 2 would be able to even overtake it at all.
    Oh gosh, I'm so sorry the second particle travels along the same line with an acceleration of 6m/s^2
    • Community Assistant
    Online

    20
    ReputationRep:
    Community Assistant
    (Original post by Rhiannemahey)
    I get that for particle 2 the time is t-2 because it is 2 seconds later but how do you start this question?
    You want to write down SUVAT for both particles respectively, then you want to equate their displacements and find the time when they're at the same place, and that's the instant when particle 2 will overtake particle 1. Find what the displacement is at this time.
    Offline

    10
    ReputationRep:
    Do the suvat s=ut+at^2 and do the other suvat with where t Is (t-2) then expand then then have them equal each other then solve for T which is where they are both a equal distance from the point
    • Thread Starter
    Offline

    5
    ReputationRep:
    (Original post by Hasham123)
    Do the suvat s=ut+at^2 and do the other suvat with where t Is (t-2) then expand then then have them equal each other then solve for T which is where they are both a equal distance from the point
    I have worked out that t=1 and t=6 but what do I do next?
    Offline

    15
    ReputationRep:
    (Original post by Rhiannemahey)
    I have worked out that t=1 and t=6 but what do I do next?
    substitute back into original equation
    • Community Assistant
    Online

    20
    ReputationRep:
    Community Assistant
    (Original post by Rhiannemahey)
    I have worked out that t=1 and t=6 but what do I do next?
    (Original post by will'o'wisp2)
    substitute back into original equation
    A missed obvious note is that you want the condition t-2>0 to remain true, so t>2 hence you neglect your first solution.
    Offline

    10
    ReputationRep:
    how have you got 2 t values
    u(t-2) +a(t-2)^2 =ut+at^2 expand brackets then rearrange to get 1 value for t
    Posted on the TSR App. Download from Apple or Google Play
    Offline

    15
    ReputationRep:
    (Original post by RDKGames)
    A missed obvious note is that you want the condition t-2>0 to remain true, so t>2 hence you neglect your first solution.
    ah yes because if t=2 then they've travelled the same distance gotcha, still going ok on the good ol m1 suvat :P
    (Original post by Hasham123)
    how have you got 2 t values
    u(t-2) +a(t-2)^2 =ut+at^2 expand brackets then rearrange to get 1 value for t
    simultaneous equations
    Offline

    10
    ReputationRep:
    Why have you used simaltanius equations they equal the same thing s so you can say they equal each other then rearrange for t
    • Thread Starter
    Offline

    5
    ReputationRep:
    (Original post by Hasham123)
    how have you got 2 t values
    u(t-2) +a(t-2)^2 =ut+at^2 expand brackets then rearrange to get 1 value for t
    Isn't the formula s=ut + 1/2at^2
    Offline

    10
    ReputationRep:
    Yes sorry about the mistake
    • Thread Starter
    Offline

    5
    ReputationRep:
    (Original post by will'o'wisp2)
    substitute back into original equation
    Thank you I got the answer to be 60m is that correct because I don't think it is
    • Community Assistant
    Online

    20
    ReputationRep:
    Community Assistant
    (Original post by Rhiannemahey)
    Thank you I got the answer to be 60m is that correct because I don't think it is
    How did you get that..?
    Offline

    15
    ReputationRep:
    (Original post by Rhiannemahey)
    Thank you I got the answer to be 60m is that correct because I don't think it is
    hmmm.... when i stick 6 into p1, i get 48m from O and i get the same for p2 :/

    RDKGames sort me out fam i can't finish it xD
 
 
 
Reply
Submit reply
Turn on thread page Beta
Updated: November 12, 2017

University open days

  1. University of Cambridge
    Christ's College Undergraduate
    Wed, 26 Sep '18
  2. Norwich University of the Arts
    Undergraduate Open Days Undergraduate
    Fri, 28 Sep '18
  3. Edge Hill University
    Faculty of Health and Social Care Undergraduate
    Sat, 29 Sep '18
Poll
Which accompaniment is best?
Useful resources

Make your revision easier

Maths

Maths Forum posting guidelines

Not sure where to post? Read the updated guidelines here

Equations

How to use LaTex

Writing equations the easy way

Student revising

Study habits of A* students

Top tips from students who have already aced their exams

Study Planner

Create your own Study Planner

Never miss a deadline again

Polling station sign

Thinking about a maths degree?

Chat with other maths applicants

Can you help? Study help unanswered threads

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

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