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This will be used as part of your Personal Professional Portfolio once graded.
Objective:
Prepare a presentation or a paper using research, basic comparative analysis, data organization and application of economic information. You will make an informed assessment of an economic climate outside of the United States to accomplish an entertainment industry objective.
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· The strongest connections happen via call, click, chat, and camera.
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· Seeking: A single source of truth
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For more information, visit-www.vavaclasses.com
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The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
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This will be used as part of your Personal Professional Portfolio once graded.
Objective:
Prepare a presentation or a paper using research, basic comparative analysis, data organization and application of economic information. You will make an informed assessment of an economic climate outside of the United States to accomplish an entertainment industry objective.
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Personal development courses are widely available today, with each one promising life-changing outcomes. Tim Han’s Life Mastery Achievers (LMA) Course has drawn a lot of interest. In addition to offering my frank assessment of Success Insider’s LMA Course, this piece examines the course’s effects via a variety of Tim Han LMA course reviews and Success Insider comments.
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https://www.hubspot.com/state-of-marketing
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· Social media is the place for search, sales, and service
· Authentic influencer partnerships fuel brand growth
· The strongest connections happen via call, click, chat, and camera.
· Time saved with AI leads to more creative work
· Seeking: A single source of truth
· TLDR; Get on social, try AI, and align your systems.
· More human marketing, powered by robots
ChatGPT is a revolutionary addition to the world since its introduction in 2022. A big shift in the sector of information gathering and processing happened because of this chatbot. What is the story of ChatGPT? How is the bot responding to prompts and generating contents? Swipe through these slides prepared by Expeed Software, a web development company regarding the development and technical intricacies of ChatGPT!
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Technology
For example, 52% agree that technology and social media have a negative impact on mental health, but when broken out by race, 61% of Whites felt technology had a negative effect, and only 48% of Hispanics thought it did.
While technology has helped us keep in touch with friends and family in faraway places, it appears to have degraded our ability to connect in person. Staying connected online is a double-edged sword since the same news feed that brings us pictures of the grandkids and fluffy kittens also feeds us news about the wars in Israel and Ukraine, the dysfunction in Washington, the latest mass shooting and the climate crisis.
Hispanics may have a built-in defense against the isolation technology breeds, owing to their large, multigenerational households, strong social support systems, and tendency to use social media to stay connected with relatives abroad.
Age and Gender
When asked how individuals rate their mental health, men rate it higher than women by 11 percentage points, and Baby Boomers rank it highest at 83%, saying it’s good or excellent vs. 57% of Gen Z saying the same.
Gen Z spends the most amount of time on social media, so the notion that social media negatively affects mental health appears to be correlated. Unfortunately, Gen Z is also the generation that’s least comfortable discussing mental health concerns with healthcare professionals. Only 40% of them state they’re comfortable discussing their issues with a professional compared to 60% of Millennials and 65% of Boomers.
Race Affects Attitudes
As seen in previous research conducted by ThinkNow, Asian Americans lag other groups when it comes to awareness of mental health issues. Twenty-four percent of Asian Americans believe that having a mental health issue is a sign of weakness compared to the 16% average for all groups. Asians are also considerably less likely to be aware of mental health services in their communities (42% vs. 55%) and most likely to seek out information on social media (51% vs. 35%).
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A report by thenetworkone and Kurio.
The contributing experts and agencies are (in an alphabetical order): Sylwia Rytel, Social Media Supervisor, 180heartbeats + JUNG v MATT (PL), Sharlene Jenner, Vice President - Director of Engagement Strategy, Abelson Taylor (USA), Alex Casanovas, Digital Director, Atrevia (ES), Dora Beilin, Senior Social Strategist, Barrett Hoffher (USA), Min Seo, Campaign Director, Brand New Agency (KR), Deshé M. Gully, Associate Strategist, Day One Agency (USA), Francesca Trevisan, Strategist, Different (IT), Trevor Crossman, CX and Digital Transformation Director; Olivia Hussey, Strategic Planner; Simi Srinarula, Social Media Manager, The Hallway (AUS), James Hebbert, Managing Director, Hylink (CN / UK), Mundy Álvarez, Planning Director; Pedro Rojas, Social Media Manager; Pancho González, CCO, Inbrax (CH), Oana Oprea, Head of Digital Planning, Jam Session Agency (RO), Amy Bottrill, Social Account Director, Launch (UK), Gaby Arriaga, Founder, Leonardo1452 (MX), Shantesh S Row, Creative Director, Liwa (UAE), Rajesh Mehta, Chief Strategy Officer; Dhruv Gaur, Digital Planning Lead; Leonie Mergulhao, Account Supervisor - Social Media & PR, Medulla (IN), Aurelija Plioplytė, Head of Digital & Social, Not Perfect (LI), Daiana Khaidargaliyeva, Account Manager, Osaka Labs (UK / USA), Stefanie Söhnchen, Vice President Digital, PIABO Communications (DE), Elisabeth Winiartati, Managing Consultant, Head of Global Integrated Communications; Lydia Aprina, Account Manager, Integrated Marketing and Communications; Nita Prabowo, Account Manager, Integrated Marketing and Communications; Okhi, Web Developer, PNTR Group (ID), Kei Obusan, Insights Director; Daffi Ranandi, Insights Manager, Radarr (SG), Gautam Reghunath, Co-founder & CEO, Talented (IN), Donagh Humphreys, Head of Social and Digital Innovation, THINKHOUSE (IRE), Sarah Yim, Strategy Director, Zulu Alpha Kilo (CA).
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From their humble beginnings in 1984, TED has grown into the world’s most powerful amplifier for speakers and thought-leaders to share their ideas. They have over 2,400 filmed talks (not including the 30,000+ TEDx videos) freely available online, and have hosted over 17,500 events around the world.
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Whether you are gearing up to get on a TED stage yourself, or just want to master the skills that so many of their speakers possess, these tips and quotes from Chris Anderson, the TED Talks Curator, will encourage you to make the most impactful impression on your audience.
See the full article and more summaries like this on SpeakerHub here: https://speakerhub.com/blog/5-presentation-tips-ted-gives-its-speakers
See the original article on Forbes here:
http://www.forbes.com/forbes/welcome/?toURL=http://www.forbes.com/sites/carminegallo/2016/05/06/5-public-speaking-tips-ted-gives-its-speakers/&refURL=&referrer=#5c07a8221d9b
ChatGPT and the Future of Work - Clark Boyd Clark Boyd
Everyone is in agreement that ChatGPT (and other generative AI tools) will shape the future of work. Yet there is little consensus on exactly how, when, and to what extent this technology will change our world.
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Friction (2) [compatibility mode]
1. Friction
Cause of dry friction
Contact between two surfaces.
Hence first task in a friction problem is correct
identification of contact surfaces
Identify the surface, the normal and the tangential
vectors.
Also important is to get an idea of probable direction
of relative motion
The contact force acts along the normal.
Gravity is the most common cause of normal force.
Friction acts along the tangent plane opposite to the
direction of relative motion
Normal
Relative velocity
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2. Friction
Normal
Relative velocity
Friction problems are
essentially equilibrium
problems with one f the
forces being functions of
another
N
Fr=f(N,V)
Fr=f(N,V)
N
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3. The correct way of writing the dry friction force
V ˆ
Fr N N V
V
N=Normal force vector
V=Relative velocity vector of the body
m= coefficient of dry friction or Coulomb
friction
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4. Problem 1
Knowing that the coefficient of friction between the 13.5
kg block and the incline is ms = 0.25, determine
a) the smallest value of P required to maintain the block in
equilibrium,
b) the corresponding value of b.
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5. Problem 1 y
N cos60 mg f sin60 P sin 0
N sin60 f cos 60 P cos 0
f N x
mg sin60 f
P
sin sin60 cos cos 60
N cos60 mg N sin60 P sin 0
mg P sin
N
cos 60 sin60
N sin60 N cos60 P cos 0
mg P sin
sin60 cos 60 P cos 0
cos 60 sin60
mg P sin sin60 cos60 P cos cos 60 sin60 0
mg sin60 cos60 P sin sin60 cos 60 P cos cos60 sin60 0
P sin60 sin cos60 sin cos60 cos sin60 cos mg sin60 cos60
sin60 cos 60
P mg
cos 60 sin 60
1 cos 60 sin 60
mg
P sin60 cos 60
d 1 d
P 0 d cos 60 sin 60 0
d
d
sin60 sin cos 60 sin cos60 cos sin60 cos 0
d
sin60 cos cos60 cos cos 60 sin sin60 sin 0
sin60 cos 60 o
tan 2.614 69
cos60 sin60
P mg
sin 60 cos60 mg
0.866 0.125 0.72mg
cos 60 sin 60 cos 9 sin 9
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6. Problem 2
Knowing that P = 110 N, determine the range of values value of q
for which equilibrium of the 8 kg block is maintained.
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7. Problem 2
y y
x x
mg mg
P cos N 0
P cos N 0
P sin mg f 0
P sin mg f 0
f N
f N
N P cos
N P cos
P sin mg N 0
P sin mg N 0
P sin mg P cos 0
P sin mg P cos 0
P sin cos mg
P sin cos mg
mg
mg P
P sin cos
sin cos
Hence
Hence
upward movement will not start before
downward movement will not start before
mg
mg P
P sin s cos
sin k cos
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8. Problem 3
The coefficients of friction are ms = 0.40 and mk = 0.30 between all
the surfaces of contact. Determine the force P for which
motion of the 27 kg block is impending if cable
a) is attached as shown,
b) is removed
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9. Problem 3
v
T N1
f1
m1g f1
N1 T
m2g f2
N2
T N1 0
N 1 m1 g 0
T N 1 , N 1 m1 g
T m1 g
T N1 N 2 P 0
N 2 N 1 m2 g 0
N 2 N 1 m 2 g 0 N 2 m1 m 2 g
T N1 N 2 P 0
m 1 g m1 g m1 m 2 g P 0
P 3 m1 g m 2 g
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10. Problem 3
v
0 N1
f1
m1g f1
N1 0
m2g f2
N2
T N 1 m1 a
Now T 0 N 1 m1 a
N 1 m1 g 0
N 1 m1 g
N1 N2 P 0
N 2 N 1 m2 g 0
N 2 N 1 m 2 g 0 N 2 m1 m2 g
N1 N2 P 0
m1 g m 1 m 2 g P 0
P 2 m1 g m2 g
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11. Additional Problems
The 8 kg block A and the 16 kg block B are at rest on an
incline as shown. Knowing that the coefficient of static
friction is 0.25 between all surfaces of contact, determine the
value of q for which motion is impending.
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12. Toppling
The magnitude of the force P is slowly increased.
Does the homogeneous box of mass m slip or tip
first? State the value of P which would cause each
occurrence.
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13. Slip or topple?
mg
f1 f2
N1 N2
P cos 30 N 1 N 2 0
P sin 30 N 1 N 2 mg 0
P cos 30 d mg d N 2 2d 0
P cos 30 N 1 N 2 N 1 N 2
P sin 30 N 1 N 2 mg
P cos 30 mg 2 N 2
P sin 30 N 1 N 2 mg P cos 30 mg
P sin 30 P cos 30 mg P sin 30 cos 30 mg
mg
P
sin 30 cos 30
0.5mg
P 0.448mg
0.25 0.866
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14. Slip or topple?
mg
f1 f2
N1 N2
P cos 30 f 2 0
P sin 30 N 2 mg 0
P cos 30 d P sin 30 2d mg d 0
P cos 30 f 2
P sin 30 N 2 mg
P cos 30 2P sin 30 mg 0
P cos 30 2 sin 30 mg
mg
P
cos 30 2 sin 30
mg
P 0.536mg
0.866 1
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18. Wedge
f=mN
P
q
N mg
P f cos N sin 0
f sin N cos mg 0
f N
mg
N sin N cos mg 0 N
sin cos
P N cos N sin 0
cos sin
P cos sin N mg
sin cos
P tan
mg tan 1
P tan tan
tan
mg tan tan 1
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19. A screw thread is a wedge
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20. A screw thread is a wedge
M=Pa
Q=Pa/r
= equivalent force
W
Q
N
f=mN
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21. A screw thread is a wedge
W
Q
N
q f=mN
Q f cos N sin 0
f sin N cos W 0
f N
W
N sin N cos W 0 N
sin cos
Q N cos N sin 0
cos sin
Q cos sin N W
sin cos
Q tan
W 1 tan Pa tan
Wr 1 tan
1 P
if tan
W
Screw locks
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22. A screw thread is a wedge
The
W
P
N
q f=mN
1 Pa
tan Screw locks
Wr
1 Wr
0
tan Pa
There is a critical value of friction
coefficient beyond which the thread
does not move irrespective of the
force applied.
This happens when a screw is not
maintained properly. Because of dirt
and rust m becomes more than
critical.
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23. A screw thread is a wedge
W
N
f=mN
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24. A screw thread is a wedge
W
N
q f
For no movement
f cos N sin 0
f sin N cos W 0
Self locking
f sin
N cos
sin
tan
cos
Therefore after raising the load if we
let go of the screw the load will not
cause the screw to unscrew by itself.
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25. Terminologies
Lead (L)
2pr
Pitch (p)
Lead L np
where
n=no. of parallely running threads = starts
L
tan =
2 r
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26. Turnbuckle
T1 T2
Used to apply tension.
The sleeve is rotated to pull the
threads together.
M tan
T2 T1 r 1 tan
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27. An improved screw jack
W
q
q
W
T
T T
T
2T cos q
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28. An improved screw jack
W
f
f
M=Pa
W=2T cos f
Pa cos sin
Wr sin cos
M cos sin
2Tr cos sin cos
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29. Worm gear
MG
M0/R
R N
M f
MG
M G WR W
R
Pa tan
Wr 1 tan
M tan
MG 1 tan
r
R
MR tan
M G r 1 tan
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30. Belt drives
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31. Belt drives
F x
0 T cos F T T cos 0
2 2
Fy 0 T sin 2 N T T sin 2 0
F s N
T cos F T T cos 0
2 2
T cos F T cos T cos 0
2 2 2
F T cos 0 T cos F s N
2 2
T sin N T T sin 0
2 2
T sin N T sin T sin 0
2 2 2
2T sin N T sin 0
2 2
2T sin N 0 2T sin N
2 2
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32. Belt drives
T cos s N
2
2T sin N
2
T cos 2T s sin
2 2
sin
1 T 2
cos s
2T 2
sin
1 T 2
Lim cos Lim
0 ,T 0 2T 2 0 ,T 0 s
1 dT
1 s
2T d 2
dT d
T s
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33. Belt drives
Belt is just about to
slide to the right
dT d
T s
T2
dT
s d T2
e s T e s T
T T 10 2 1
T2
T1
lnT
T1
s 0
Torque required to drive the pulley
lnT lnT2 1
s
T2 T1 e s 1 T
ln T
2
1
T 1
s
T
2 es
T
1
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34. Belt drives : Important points
T
2 es
T
1
Angle b must be expressed in
radians
Larger tension occurs at the end of
the belt where motion is about to begin
or is already moving
T2 is used to denote the larger
tension
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35. Belt drives
A B
q
q
A B
q
q
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36. Belt drives
T2
T2
exp 2 ???
T1
A Always check
for mb value for
each pulley in a
system. The one
with the
T1
smallest mb
q
value will
determine the
Which expression is tensions.
correct???? Is T2>T1
Or T1>T2.
One pulley must slip. T2
Friction force is larger
for the larger pulley since
angle of wrap is larger.
Hence smaller pulley
B
slips and determines the
tension
T1 q
exp 2 ???
T1
T2
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37. Band brakes
Important!!!
In pulleys the belt
is mobile and
tries to drive the
pulley. Here the
drum moves and
tries to move the
belt. Hence the
sense of slack is
opposite to that
for a pulley.
T1
T2
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38. Band brakes
y
The drum rotates towards the right.
Ry If this were a pulley the slack side
would be on the left. But here as the
Rx
Mext drum is the moving part, the slack
x side is on the left.
T1 T2 exp( k )
T1 M 0 M ext
r T1 T2 0
T2 M ext T1 T2 r
F x
0 Rx T2 sin( )
F y
0 R y T1 T2 cos( )
a -p
F x
0 Bx T2 sin( ) 0
Bx T2 sin
F y
0 B y T2 cos( ) T1 P 0
B y T2 cos T1 P 0
M B
0 cT2 bT1 a b P 0
bT1 cT2
P
ab
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39. Band brakes
T1 T2 exp( k ), M ext T1 T2 r
bT1 cT2
Bx T2 sin , B y T2 cos T1 P 0 , P
ab
M ext T1 T2 r T2 exp( k ) T2 r exp( k ) 1T2 r
M ext
T2
exp( k ) 1 r
bT1 cT2 bT2 exp( k ) cT2 bexp( k ) c
P T2
ab ab ab
bexp( k ) c M ext
P exp( ) 1 r
ab k
c
1 exp( k )
b M ext
P
1 exp( k ) a
1 r
b
c
Now 1 exp( ) 0 P 0 if 1 exp( ) 0
k b k
k
P 0 iff b > ce > ce s s k
Otherwise P is negative
negative.
Which means no force is required for braking!
Hence self locking occurs.
Since Mext is equal in magnitude to the torque required
for braking it is also called the braking torque.
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40. Clutches
Assume pressure is uniform over the contact zone
P
p=
R2
Consider a small element of width dr at a radial distance r
and spanning an angle d
dA r dr d
dF pdA prdrd
dM rdF r prdrd pr 2 drd
2
2 R
2
r 3 R p 3 2
M pr drd p 2 R pR 3
0 0 3 0 0
3 3
2 P 3 2
M R PR
3 R2 3
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41. Clutches
Assume pressure is uniform
over the contact zone
P
p=
r12 r02
Consider a small element of spanning angle d at a radial distance r
dA r dr d
dF pdA prdrd
dM rdF r prdrd pr 2 drd
2
2 r1 r 3 r
1
p 3 2
pr drd p 3 3 r1 r0 2 3 p r1 r0
2 3 3 3
M
0 r
0 r 0
0
2 P 3
2 1
r r0
3
M
3 r1 r0
2
2 r13 r03
M P 2
3 r1 r02
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42. Disc Brake
dq
Assume pressure is uniform over the contact zone
Area of a whole circle (spanning 2 radians) = r 2
r2 r2
Area of a sector = =
2 2
2P
p=
R02 Ri2
Consider a small element of spanning angle d at a radial distance r
dA r dr d
dF pdA prdrd
dM rdF r prdrd pr 2 drd
Ro r 3 R o
p 3 p
2
M pr drd p Ro Ri3 3 Ro3 Ri3
0 R i 3 R 0
i
3
p 3
M Ro Ri3 Ro3 Ri3 R2P R 2
3 3 02 i
2 Ro Ri
3 3
M
3 R02 Ri2
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43. Thrust bearing
P
d
q2
q q
d1
P
q d1
q
d1
d2
q
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44. Thrust bearing
y dl
df X
dN
O x
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45. Thrust bearing y dl
r dr
df X
dN
O x
Assume pressure is uniform over the contact zone
P
P= R2 2 R1 2 p p=
R2 2 R1 2 What
R2 2
about q
M rdf
R1 0
=0?
dN pdA prd dl , dl drcosec
dN prd dl prd dr cosec pcosec d rdr
df dN pcosec d rdr
R2 2
N pcosec d rdr
R1 0
R2 R2 R2
2 r2
N p cosec 0
rdr 2 pcosec rdr 2 pcosec
2 R
R1 R 1 1
N pcosec R2 2 R1 2
R2 2 R2 2
M rdf r rpcosec d rdr
R1 0 R1 0
R2 R2 R2
2 r3
pcosec
2 2
M 0
r dr 2 pcosec r dr 2 pcosec
R1 R 1 3 R 1
2 P R2 R1
3 3
2 p
M R2 R1 3sin R 2 R 2
3 3
3sin 2 1
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46. Torque wrench
r T1 T2 aP
Smallest m for self locking ?
T2
T1 T1 T2 exp 2
N
mN
T1 N cos T2 N sin 0
P N sin T2 N cos 0
mN
T1
N
T2
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47. Torque wrench
Condition for self locking ?
T1 T2 exp 2
r T1 T2 aP
T1 N cos T2 N sin 0
P N sin T2 N cos 0
T2 T1 sin cos P cos sin
T1 T1 sin cos P cos sin exp 2
T1 T1 sin cos exp 2 P cos sin exp 2
T1 sin cos exp 2 1 P cos sin exp 2
P cos sin exp 2
P cos sin
T1
sin cos exp 2 1 sin cos exp 2
aP
r T1 T2 aP T1
r 1 exp 2
aP P cos sin
r 1 exp 2
sin cos exp 2
r cos sin a sin cos
exp 2
r cos sin a
r cos sin a
exp 2
r cos sin a sin cos
a
1 cos sin
ln r
a
2
cos sin sin cos
r
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48. Band brakes
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49. Band brakes
TB T1 T3
B
T1 T3
T4
T2
75 75
T2 T1 exp T1 exp 0.25
180 180
T2 1.39T1
135 135
T3 T4 exp T4 exp 0.25
180 180
T4 0.55T3
M 0 T3 T4 T2 T1 R
Consider the pin B
F x
0 T1 cos 45 T3 cos 45 T1 T3
F y
0 T1 cos 45 T3 cos 45 TB 2T1 cos 45 TB 2T1 TB
T2 1.39T1 ,T3 T1 ,T4 0.55T1
Thus the largest tension is T2 5.6 T1 T3 4.03,T4 2.22,TB 5.7
M 5.6 2.22 R 3.38 0.16 0.54 KNm 540 Nm
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50. Problems
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51. Tip or Slide
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52. Problems
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53. Problems
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