Turn on thread page Beta
    • Community Assistant
    • Study Helper
    Offline

    20
    ReputationRep:
    Community Assistant
    Study Helper
    (Original post by Jiffylemmon)
    22xs=t?
    You've got the formula mixed up.

    s=ut

    u = 22
    t = t
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by notnek)
    You've got the formula mixed up.

    s=ut

    u = 22
    t = t
    Okay so it's s/22=t But how can I find s or t with only one piece of information? (It's really strange that I cannot not even come close to answering this question since I just answer an harder question before this that also requires the use of a time graph it was worth up to 12 marks and this is only 3).
    • Community Assistant
    • Study Helper
    Offline

    20
    ReputationRep:
    Community Assistant
    Study Helper
    (Original post by Jiffylemmon)
    Okay so it's 22/s=t But how can I find s or t with only one piece of information?
    Sorry that's wrong.

    s = ut.

    You have said that u/s = t which is incorrect.

    You should be finding the distance in terms of t. This means that you use 't' as the value for time.

    s = ut

    u = 22
    t = t

    So s = 22t.

    The distance travelled is 22t. Does this make sense?
    • Community Assistant
    • Study Helper
    Offline

    20
    ReputationRep:
    Community Assistant
    Study Helper
    (Original post by Jiffylemmon)
    Okay so it's s/22=t But how can I find s or t with only one piece of information? (It's really strange that I cannot not even come close to answering this question since I just answer an harder question before this that also requires the use of a time graph it was worth up to 12 marks and this is only 3).
    It's not strange at all. This 3 mark question was designed for someone who had already drawn a speed-time graph.
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by notnek)
    Sorry that's wrong.

    s = ut.

    You have said that u/s = t which is incorrect.

    You should be finding the distance in terms of t. This means that you use 't' as the value for time.

    s = ut

    u = 22
    t = t

    So s = 22t.

    The distance travelled is 22t. Does this make sense?
    yes I'm sorry about that, i usually don't stay up this late doing homework. I was suppose to type it in the other way round my bad.
    So now that I know 22t=s where should I go?
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by notnek)
    It's not strange at all. This 3 mark question was designed for someone who had already drawn a speed-time graph.
    But the other one also was designed for someone who had already drawn an time graph
    • Community Assistant
    • Study Helper
    Offline

    20
    ReputationRep:
    Community Assistant
    Study Helper
    (Original post by Jiffylemmon)
    yes I'm sorry about that, i usually don't stay up this late doing homework. I was suppose to type it in the other way round my bad.
    So now that I know 22t=s where should I go?
    Next find the distance for the third region.

    The time for this section is 120 - t - 30. Does this make sense?

    So you have:

    u = 22
    v = 0
    t = 90 - t

    Can you find s?
    • Community Assistant
    • Study Helper
    Offline

    20
    ReputationRep:
    Community Assistant
    Study Helper
    (Original post by Jiffylemmon)
    But the other one also was designed for someone who had already drawn an time graph
    So for that one you were just lucky that another method could be used that was simple.
    Offline

    3
    ReputationRep:
    (Original post by notnek)
    So for that one you were just lucky that another method could be used that was simple.
    I got 75 seconds, is that right?
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by notnek)
    Next find the distance for the third region.

    The time for this section is 120 - t - 30. Does this make sense?

    So you have:

    u = 22
    v = 0
    t = 90 - t

    Can you find s?
    S=(22+0/2)x90-t? So s=45?
    Offline

    3
    ReputationRep:
    (Original post by Jiffylemmon)
    S=(22+0/2)x90-t?
    I think I have the right answer, if you want I can post a full solution with explanations for each line of working.
    • Community Assistant
    • Study Helper
    Offline

    20
    ReputationRep:
    Community Assistant
    Study Helper
    (Original post by Jiffylemmon)
    S=(22+0/2)x90-t?
    Yes and that can be simplified.

    Finally add up all the distances and set the sum equal to 2145 since this is the total distance.

    Then solve to find t.
    Offline

    3
    ReputationRep:
    (Original post by notnek)
    Yes and that can be simplified.

    Finally add up all the distances and set the sum equal to 2145 since this is the total distance.

    Then solve to find t.
    For the record, I like what you're doing. You're not just telling him the answer, you're giving him hints :P
    • Community Assistant
    • Study Helper
    Offline

    20
    ReputationRep:
    Community Assistant
    Study Helper
    (Original post by jacobe)
    I think I have the right answer, if you want I can post a full solution with explanations for each line of working.
    Please don't do that. You can see how hard that Jiffylemmon has worked in this thread so let them finish it.

    Plus it's against the rules to post full solutions.
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by notnek)
    Yes and that can be simplified.

    Finally add up all the distances and set the sum equal to 2145 since this is the total distance.

    Then solve to find t.
    Is s 45?
    Offline

    3
    ReputationRep:
    (Original post by notnek)
    Please don't do that. You can see how hard that Jiffylemmon has worked in this thread so let them finish it.

    Plus it's against the rules to post full solutions.
    Ok. I think you're making it way too complicated though.
    • Community Assistant
    • Study Helper
    Offline

    20
    ReputationRep:
    Community Assistant
    Study Helper
    (Original post by jacobe)
    Ok. I think you're making it way too complicated though.
    Ok, please give your method. I considered the speed-time graph in my head and developed a method from there. I'm sure there are other (maybe better) ways to do it.
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by jacobe)
    I think I have the right answer, if you want I can post a full solution with explanations for each line of working.
    Thanks for the offer but notnek has been helping me out so much(big thanks!) it would be a waste to see the soloution when I'm this close.
    • Thread Starter
    Offline

    2
    ReputationRep:
    Erm I'm guessing s=45 isn't right?
    • Community Assistant
    • Study Helper
    Offline

    20
    ReputationRep:
    Community Assistant
    Study Helper
    (Original post by Jiffylemmon)
    Is s 45?
    Which s? The final goal of the question is to find t, not s.

    Post your working.
 
 
 
Reply
Submit reply
Turn on thread page Beta
Updated: September 10, 2015

University open days

  1. Norwich University of the Arts
    Postgraduate Open Days Postgraduate
    Thu, 19 Jul '18
  2. University of Sunderland
    Postgraduate Open Day Postgraduate
    Thu, 19 Jul '18
  3. Plymouth College of Art
    All MA Programmes Postgraduate
    Thu, 19 Jul '18
Poll
Is the Big Bang theory correct?
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.