You are Here: Home >< Maths

# m3:what if a particle is attached to a stretched string whilst in a rough surface?

Announcements Posted on
Four hours left to win £100 of Amazon vouchers!! Don't miss out! Take our short survey to enter 24-10-2016
1. Should we assume at m3 level that the particle is moving under constant deceleration only due to the rough surface? A problem in the book had this condition and the solution assumed the particle was only experiencing deceleration due to the rough surface and not due to both the stretched string and rough surface. Attached the question(question 8), solution and my working showing that distance travelled would cause particle to enter the stretched string territory.
Attached Images

2. (Original post by thebrahmabull)
Should we assume at m3 level that the particle is moving under constant deceleration only due to the rough surface? A problem in the book had this condition and the solution assumed the particle was only experiencing deceleration due to the rough surface and not due to both the stretched string and rough surface. Attached the question(question 8), solution and my working showing that distance travelled would cause particle to enter the stretched string territory.
It looks as if the book has failed to take into account that the string will stretch again. Just assumed that it doesn't and that all the motion on the rough surface will take place whilst the string is unstretched. This is not the case, as you've discovered - book's in error.

For the sake of doing the question, you'll have to assume that once the string goes slack, someone steps in and cuts it.
3. (Original post by ghostwalker)
It looks as if the book has failed to take into account that the string will stretch again. Just assumed that it doesn't and that all the motion on the rough surface will take place whilst the string is unstretched. This is not the case, as you've discovered - book's in error.

For the sake of doing the question, you'll have to assume that once the string goes slack, someone steps in and cuts it.
I see. The situation is quite difficult here. I hope it doesnt come up in an exam. Thanks a lot!

## Register

Thanks for posting! You just need to create an account in order to submit the post
1. this can't be left blank
2. this can't be left blank
3. this can't be left blank

6 characters or longer with both numbers and letters is safer

4. this can't be left empty
1. Oops, you need to agree to our Ts&Cs to register

Updated: May 14, 2016
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:
Today on TSR

### Who is getting a uni offer this half term?

Find out which unis are hot off the mark here

Poll
Useful resources

### Maths Forum posting guidelines

Not sure where to post? Read here first

### How to use LaTex

Writing equations the easy way

### Study habits of A* students

Top tips from students who have already aced their exams