Hey there! Sign in to join this conversationNew here? Join for free
    • Thread Starter
    Offline

    0
    ReputationRep:
    Question is attached. It's driving me nuts, I can't understand what is going on at all. After being released from C, the particle starts moving with SHM, with the centre of oscillation at the midpoint of AB. It says the amplitude is 0.4m, but I would have thought that C would be the 'extreme' point of the oscillation, i.e. the particle hits C and turns back around, making the amplitude 0.5m.

    Also, a general question - I have no idea how to work out where the centre of oscillation is. When it's just one spring, I know it's where the spring is at its natural length, but when a particle is attached to two springs which are stretched out, I'm baffled. Does the point where each spring is at its natural length have any significance at all?
    Attached Images
     
    • Study Helper
    Offline

    13
    (Original post by bzzz)
    Question is attached. It's driving me nuts, I can't understand what is going on at all. After being released from C, the particle starts moving with SHM, with the centre of oscillation at the midpoint of AB. It says the amplitude is 0.4m, but I would have thought that C would be the 'extreme' point of the oscillation, i.e. the particle hits C and turns back around, making the amplitude 0.5m.
    Book is wrong IMHO. Amplitude is 0.5, as that is the distance between the release point (where the velocity is zero) and the centre of oscillation (the midpoint of AB)

    Also, a general question - I have no idea how to work out where the centre of oscillation is. When it's just one spring, I know it's where the spring is at its natural length, but when a particle is attached to two springs which are stretched out, I'm baffled. Does the point where each spring is at its natural length have any significance at all?
    The centre of oscillation is where the net force acting on the particle is zero. Here it is the midpoint of AB, since the two springs are identical, and at the midpoint they have the same extension so exert equal and opposite forces, and hence the net force is zero, hence it is the centre of oscillation.
    • Thread Starter
    Offline

    0
    ReputationRep:
    (Original post by ghostwalker)
    Book is wrong IMHO. Amplitude is 0.5, as that is the distance between the release point (where the velocity is zero) and the centre of oscillation (the midpoint of AB)

    The centre of oscillation is where the net force acting on the particle is zero. Here it is the midpoint of AB, since the two springs are identical, and at the midpoint they have the same extension so exert equal and opposite forces, and hence the net force is zero, hence it is the centre of oscillation.
    Excellent, noted, thanks
 
 
 
  • See more of what you like on The Student Room

    You can personalise what you see on TSR. Tell us a little about yourself to get started.

  • Poll
    Will you be richer or poorer than your parents?
    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
  • See more of what you like on The Student Room

    You can personalise what you see on TSR. Tell us a little about yourself to get started.

  • 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

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