You are Here: Home >< Maths

# M1 connected bodies Watch

1. https://2802a3b1a650824d2586fd3336bd...%20Edexcel.pdf

question 7 part c

my diagram has a big 800kg square on the right and a stick in the middle connected to a 200 kg square
on the 800kg square , it has 400N and FN and tension of 100N in the towbar all going left
on the 200kg square it has 100N in the towbar and just 200N going to the left

calculating for the acceleration i used f=ma on the trailer(200kg square)
200-100=200a defining positive as left
thus a=0.5ms^-1
so it's decelerating but this answer is wrong where did it go oh so wrong?
2. (Original post by Big white)
https://2802a3b1a650824d2586fd3336bd...%20Edexcel.pdf

question 7 part c

my diagram has a big 800kg square on the right and a stick in the middle connected to a 200 kg square
on the 800kg square , it has 400N and FN and tension of 100N in the towbar all going left
on the 200kg square it has 100N in the towbar and just 200N going to the left

calculating for the acceleration i used f=ma on the trailer(200kg square)
200-100=200a defining positive as left
thus a=0.5ms^-1
so it's decelerating but this answer is wrong where did it go oh so wrong?
let me draw you a diagram

Edit: here...

there is no tension in the car, its both thrust.
3. (Original post by KloppOClock)
let me draw you a diagram

Edit: here...

there is no tension in the car, its both thrust.
I didn't say there was any tension in the car i said it was in the towbar so this is how i've drawn my diagram
Attached Images

4. (Original post by Big white)
I didn't say there was any tension in the car i said it was in the towbar so this is how i've drawn my diagram
there is no tension, there is only thrust
5. (Original post by KloppOClock)
there is no tension, there is only thrust
but it's in the towbar??? so surely the diagram i've drawn is right?
6. When decelerating, the tension becomes thrust as the objects want to move closer together and the towbar prevents this by pushing outwards (not sure if this is the truth but it's how I think about it), thrust acts outwards from the center so your "T" arrows should be flipped.
7. (Original post by Big white)
but it's in the towbar??? so surely the diagram i've drawn is right?
The car is slowing down from high speed. As the tow bar cannot compress, there is thrust.

Thrust is basically the opposite of tension, you either have thrust or tension depending on the acceleration
8. (Original post by JN17)
When decelerating, the tension becomes thrust as the objects want to move closer together and the towbar prevents this by pushing outwards (not sure if this is the truth but it's how I think about it), thrust acts outwards from the center so your "T" arrows should be flipped.
ah... thanks so much! I've gotten it now
9. (Original post by KloppOClock)
The car is slowing down from high speed. As the tow bar cannot compress, there is thrust.

Thrust is basically the opposite of tension, you either have thrust or tension depending on the acceleration
Thanks a lot i've got it now

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:
Updated: June 7, 2016
Today on TSR

### What is the latest you've left an assignment

And actually passed?

### Simply having a wonderful Christmas time...

Discussions on TSR

• Latest
• ## 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
Useful resources

### Maths Forum posting guidelines

Not sure where to post? Read the updated guidelines here

### How to use LaTex

Writing equations the easy way

### Study habits of A* students

Top tips from students who have already aced their exams

## Groups associated with this forum:

View associated groups
Discussions on TSR

• Latest
• ## 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

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