Statics Help A Level Mathematics Mechanics Watch

Rolls_Reus_0wner
Badges: 18
Rep:
?
#1
Report Thread starter 4 weeks ago
#1
Hi, I'm doing this question to find out what tan theta is. I'm not sure what to do next after taking moments from A
Posted on the TSR App. Download from Apple or Google Play
0
reply
Rolls_Reus_0wner
Badges: 18
Rep:
?
#2
Report Thread starter 4 weeks ago
#2
Name:  image-7fcdd608-b0b8-4cc4-81d5-87c9950f2f7e445076846457486887-compressed.jpg.jpeg
Views: 5
Size:  76.0 KB Question 8. I'm posting my working out below
Posted on the TSR App. Download from Apple or Google Play
0
reply
Rolls_Reus_0wner
Badges: 18
Rep:
?
#3
Report Thread starter 4 weeks ago
#3
Name:  image-9f57dc77-6c38-439d-b967-ad1aaaf46caf8015316992590907779-compressed.jpg.jpeg
Views: 3
Size:  38.7 KB
Posted on the TSR App. Download from Apple or Google Play
0
reply
Notnek
  • Community Assistant
Badges: 20
Rep:
?
#4
Report 4 weeks ago
#4
(Original post by Rolls_Reus_0wner)
Hi, I'm doing this question to find out what tan theta is. I'm not sure what to do next after taking moments from A
You don't seem to have posted your working showing you taking moments. Can you post that please?
0
reply
Rolls_Reus_0wner
Badges: 18
Rep:
?
#5
Report Thread starter 4 weeks ago
#5
(Original post by Notnek)
You don't seem to have posted your working showing you taking moments. Can you post that please?
Attachment 798694

I think i got it now. the solution bank took moments from X (will send a pic of that). how did i get the same answer?
Posted on the TSR App. Download from Apple or Google Play
Last edited by Rolls_Reus_0wner; 4 weeks ago
0
reply
Notnek
  • Community Assistant
Badges: 20
Rep:
?
#6
Report 4 weeks ago
#6
(Original post by Rolls_Reus_0wner)
Name:  image-698ace25-45d0-472b-ae54-3ac8306a46f6982747722934064217-compressed.jpg.jpeg
Views: 7
Size:  31.8 KB
First tidy that up by cancelling the 'a' on both sides. Now I look at what we're trying to get to and I see a \tan \theta so my next thought is to divide this equation by \cos \theta. Try that next.

Your aim after that will be to eliminate all the non-\mu variables by using all of the equations that you've generated. Please post your full attempt if you get stuck.
Last edited by Notnek; 4 weeks ago
0
reply
Notnek
  • Community Assistant
Badges: 20
Rep:
?
#7
Report 4 weeks ago
#7
Rolls_Reus_0wner I just looked at your moments equation again and one of your (\sin \theta)s is wrong. Please check your equation again.
0
reply
Rolls_Reus_0wner
Badges: 18
Rep:
?
#8
Report Thread starter 4 weeks ago
#8
(Original post by Notnek)
Rolls_Reus_0wner I just looked at your moments equation again and one of your (\sin \theta)s is wrong. Please check your equation again.
Name:  image-4522b385-a37f-42c1-a042-8c97c6a6e32d2381289675721011512-compressed.jpg.jpeg
Views: 7
Size:  32.0 KB
Posted on the TSR App. Download from Apple or Google Play
0
reply
Notnek
  • Community Assistant
Badges: 20
Rep:
?
#9
Report 4 weeks ago
#9
(Original post by Rolls_Reus_0wner)
Name:  image-4522b385-a37f-42c1-a042-8c97c6a6e32d2381289675721011512-compressed.jpg.jpeg
Views: 7
Size:  32.0 KB
That's correct now.
0
reply
Rolls_Reus_0wner
Badges: 18
Rep:
?
#10
Report Thread starter 4 weeks ago
#10
(Original post by Notnek)
That's correct now.
Name:  image-20248119-4295-4400-9e00-9f05b8b529b04172652178744489772-compressed.jpg.jpeg
Views: 5
Size:  32.3 KB
Posted on the TSR App. Download from Apple or Google Play
0
reply
Notnek
  • Community Assistant
Badges: 20
Rep:
?
#11
Report 4 weeks ago
#11
(Original post by Rolls_Reus_0wner)
Name:  image-20248119-4295-4400-9e00-9f05b8b529b04172652178744489772-compressed.jpg.jpeg
Views: 5
Size:  32.3 KB
I'm guessing you're stuck from here? Looking at the final result, you'll clearly need to start introducing the \mu's by using the other equations.

\displaystyle \frac{R_2}{R_1} = \mu_1 looks like it will be useful...
0
reply
Rolls_Reus_0wner
Badges: 18
Rep:
?
#12
Report Thread starter 4 weeks ago
#12
(Original post by Notnek)
I'm guessing you're stuck from here? Looking at the final result, you'll clearly need to start introducing the \mu's by using the other equations.

\displaystyle \frac{R_2}{R_1} = \mu_1 looks like it will be useful...
final working: Took me an hour and half to figire this out...

Name:  image-c029adbb-4fc3-4e3b-bb5a-fb3bac2fb7612979083873790520161-compressed.jpg.jpeg
Views: 4
Size:  49.8 KB
Posted on the TSR App. Download from Apple or Google Play
1
reply
Notnek
  • Community Assistant
Badges: 20
Rep:
?
#13
Report 4 weeks ago
#13
(Original post by Rolls_Reus_0wner)
final working: Took me an hour and half to figire this out...
They're the best kind of questions - you learn so much

Im sure that your ability to tackle these long questions has improved just by doing this one. For these types of questions where they give the final result, always think about the best way to arrive at it, as I showed in posts above.
0
reply
Rolls_Reus_0wner
Badges: 18
Rep:
?
#14
Report Thread starter 4 weeks ago
#14
(Original post by Notnek)
They're the best kind of questions - you learn so much

Im sure that your ability to tackle these long questions has improved just by doing this one. For these types of questions where they give the final result, always think about the best way to arrive at it, as I showed in posts above.
One thing: how is ??? whts the proof for that?
0
reply
Notnek
  • Community Assistant
Badges: 20
Rep:
?
#15
Report 4 weeks ago
#15
(Original post by Rolls_Reus_0wner)
One thing: how is ??? whts the proof for that?
Sorry I shouldn't just have given you this equation. You wrote

\displaystyle F_1=R_2

\displaystyle F_1=\mu_1 R_1

and combining these gives

\displaystyle R_2 = \mu_1 R_1 \Rightarrow \frac{R_2}{R_1} = \mu_1

There are many different ways to go about the algebra in this question but the basic aim is to eliminate the non-\mu variables in whichever way you choose.
0
reply
Rolls_Reus_0wner
Badges: 18
Rep:
?
#16
Report Thread starter 4 weeks ago
#16
(Original post by Notnek)
Sorry I shouldn't just have given you this equation. You wrote

\displaystyle F_1=R_2

\displaystyle F_1=\mu_1 R_1

and combining these gives

\displaystyle R_2 = \mu_1 R_1 \Rightarrow \frac{R_2}{R_1} = \mu_1

There are many different ways to go about the algebra in this question but the basic aim is to eliminate the non-\mu variables in whichever way you choose.
Mind blown. thanks 4 all your help
0
reply
X

Quick Reply

Attached files
Write a reply...
Reply
new posts
Latest
My Feed

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.

Personalise

University open days

  • Edge Hill University
    Undergraduate and Postgraduate - Campus Tour Undergraduate
    Fri, 22 Mar '19
  • Birmingham City University
    Undergraduate Open Day Undergraduate
    Sat, 23 Mar '19
  • University of Bolton
    Undergraduate Open Day Undergraduate
    Sat, 23 Mar '19

Where do you need more help?

Which Uni should I go to? (95)
16.7%
How successful will I become if I take my planned subjects? (60)
10.54%
How happy will I be if I take this career? (100)
17.57%
How do I achieve my dream Uni placement? (85)
14.94%
What should I study to achieve my dream career? (57)
10.02%
How can I be the best version of myself? (172)
30.23%

Watched Threads

View All
Latest
My Feed