friction

1. S C R E W F R I C T I O N
M
R
.
M
.
S
R
E
E
D
H
A
R
,
A
S
S
I
S
T
A
N
T
P
R
O
F
E
S
S
O
R

2. SCREW THREADS
M
R
.
M
.
S
R
E
E
D
H
A
R
,
A
S
S
I
S
T
A
N
T
P
R
O
F
E
S
S
O
R

3. S C R E W F R I C T I O N
• Screws used to fix objects in place are called fasteners, and screws used to
move objects are called power screws or lead screws.
• Screw Motion and the Right-hand rule
M
R
.
M
.
S
R
E
E
D
H
A
R
,
A
S
S
I
S
T
A
N
T
P
R
O
F
E
S
S
O
R
Loosening Tightening

4. S C R E W T H R E A D S
M
R
.
M
.
S
R
E
E
D
H
A
R
,
A
S
S
I
S
T
A
N
T
P
R
O
F
E
S
S
O
R

5. • P I T C H
L E A D
H E L I X A N G L E
SCREW THREADS
M
R
.
M
.
S
R
E
E
D
H
A
R
,
A
S
S
I
S
T
A
N
T
P
R
O
F
E
S
S
O
R

6. APPLICATIONS OF SCREW THREADS
M
R
.
M
.
S
R
E
E
D
H
A
R
,
A
S
S
I
S
T
A
N
T
P
R
O
F
E
S
S
O
R

7. SCREW JACK
M
R
.
M
.
S
R
E
E
D
H
A
R
,
A
S
S
I
S
T
A
N
T
P
R
O
F
E
S
S
O
R

8. SCREW JACK
M
R
.
M
.
S
R
E
E
D
H
A
R
,
A
S
S
I
S
T
A
N
T
P
R
O
F
E
S
S
O
R