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Turbo Pascal Chain module | 1987-10-26 | 46.5 KB | 343 lines |
- DATA AREA FOR BUILDEXE FOLLOWS
- GBIGTURBO - Large Code Model. Copyright (c) 1985 by TurboPower Software.
- "All Rights Reserved. Version 1.08D
- 0123456789ABCDEFLL
- module:
- procedure:
- called from
- module: 0
- 1Out of BIGTURBO stack space or no modules loaded.
- 3Attempting to call routine in uninitialized module.
- 3Invalid FarIncoming pointer or corrupt module code.
- Program error - code
- in FarOutgoing.
- Error while calling module:
- , procedure:
- from module
- ;Select the magnitude F of the force between 10.00 and 1000
- 3newtons, and the angle ~
- the force forms with the
- <horizontal axis as measured counterclockwise from the right
- from 0 to 360 degrees.\
- Force
- MAGNITUDE AND ANGLE
- <The force ~F will be resolved into a component along HH and
- .another component along a line of your choice.
- =\Which line [AA, BB, CC, DD, or EE] do you want to use? ~[==]
- AA/BB/CC/DD/EE/
- YOUR CHOICE [A through E]
- ?We draw the triangle formed by the force ~F and its components
- ;~P and ~Q, and determine the three angles in that triangle.
- (\Since the force ~F lies along the line
- -, it has no component along HH. We thus have
- \ ~P = ~0 ~Q =
- 3\Since the force ~F lies along the line HH, it has
- no component along
- . We thus have
- \ ~P =
- ~Q = ~0.
- 6\Since the line CC that you have chosen is at a right
- ;angle to line HH, the components obtained are _rectangular
- components_.
- THE VALUE OF THE ANGLE
- THE VALUES OF THE ANGLES
- /We shall use the formulas for a right triangle.
- sin/cos/tan/
- \ P
- ~[===]
- Q
- ~[===]
- *S for SINE, C for COSINE, or T for TANGENT
- 3We shall use the law of sines to determine P and Q:
- $ _ P _ _ Q _ _
- 1` sin ~[======] sin ~[======] sin ~[======]
- THE VALUES OF THE ANGLES
- )We now solve these equations for P and Q:
-
- sin ~[======]
- sin ~[======]\
- P =
- ------------ Q =
- -----------\
- sin ~[======]
- sin ~[======]
- ANGLES
- sin ~[======]
- sin ~[======]\
- P =
- ------------ Q =
- -----------\
- sin ~[======]
- sin ~[======]
- -We shall now calculate the values of P and Q.
- \ P =
- N Q =
- (\ P = ~[======] N Q = ~[======] N
- VALUES
- -The components ~P and ~Q of the force ~F are
- therefore:
- ~P =
- ~Q =
-
- >\The coordinates of points A,B, and C have been preselected.
- 9Choose the coordinates of D (from -24.0 to +24.0 inches)
- and enter them in the table.
- 60 lb
- x (in) y (in) z (in)
- A 0.00 -40.0 0.00
- B -24.0 0.00 15.00
- C -13.00 0.00 -16.00
- D 0.00
- DIMENSIONS
- Q\We shall first express the force exerted by cable AB on point A in terms of the
- $unknown tension T(AB) in that cable.
- ]We start by computing the components and magnitude of the vector ~A~B joining points A and B:
- 6\x component = x(B) - x(A) = (-24.0) - 0.00 = -24.0 in
- 5y component = y(B) - y(A) = 0.00 - (-40.0) = 40.0 in
- 6z component = z(B) - z(A) = 15.00 - 0.00 = 15.00 in
- H\Magnitude = |~A~B| = sqrt~((-24)(-24) + (40)(40) + (15)(15)~) = 49.0 in
- >We may now express the vector ~A~B in terms of its components:
- J ~A~B = (-24.0 in) ~i + (40.0 in) ~j + (15.00 in) ~k |~A~B| = 49.0 in
- GWe divide this expression by |~A~B| to obtain the unit vector along AB:
- * ~ (AB) = -0.490 ~i + 0.816 ~j + 0.306 ~k
- <We multiply the unit vector along AB by the unknown tension
- 3T(AB) to obtain the force exerted by AB on point A:
- < ~F(AB) = -0.490 T(AB) ~i + 0.816 T(AB) ~j + 0.306 T(AB) ~k
- 4~F(AB) = -0.490T(AB)~i + 0.816T(AB)~j + 0.306T(AB)~k
- @We follow the same procedure with the force exerted by cable AC.
- 5Components of the vector ~A~C joining points A and C:
- @x component = x(C) - x(A) = ~[======] - ~[======] = ~[======] in
- X-VALUES
- @y component = y(C) - y(A) = ~[======] - ~[======] = ~[======] in
- Y-VALUES
- @z component = z(C) - z(A) = ~[======] - ~[======] = ~[======] in
- Z-VALUES
- 3We may now express ~A~C in terms of its components:
- A~A~C = (~[======] in) ~i + (~[======] in) ~j + (~[======] in) ~k
- COMPONENTS
- 4~A~C = (-13.00 in) ~i + (40.0 in) ~j + (-16.0 in) ~k
- IMagnitude = |~A~C| = sqrt~((-13)(-13) + (40)(40) + (-16)(-16)~) = 45.0 in
- <We divide ~A~C by |~A~C| to obtain the unit vector along AC:
- * ~ (AC) = -0.289 ~i + 0.889 ~j - 0.356 ~k
- <We multiply the unit vector along AC by the unknown tension
- 3T(AC) to obtain the force exerted by AC on point A:
- < ~F(AC) = -0.289 T(AC) ~i + 0.889 T(AC) ~j - 0.356 T(AC) ~k
- 4~F(AC) = -0.289T(AC)~i + 0.889T(AC)~j - 0.356T(AC)~k
- @We follow the same procedure with the force exerted by cable AD.
- 5Components of the vector ~A~D joining points A and D:
- @x component = x(D) - x(A) = ~[======] - ~[======] = ~[======] in
- X-VALUES
- @y component = y(D) - y(A) = ~[======] - ~[======] = ~[======] in
- Y-VALUES
- @z component = z(D) - z(A) = ~[======] - ~[======] = ~[======] in
- Z-VALUES
- 3We may now express ~A~D in terms of its components:
- A~A~D = (~[======] in) ~i + (~[======] in) ~j + (~[======] in) ~k
- COMPONENTS
- \~A~D = (
- in) ~i + (40 in) ~j + (
- in) ~k
- Magnitude = |~A~D| = sqrt~((
- ) + (40)(40) + (
- )~) =
- BWe shall divide ~A~D by |~A~D| to obtain the unit vector along AD.
- \ ~ (AD) =
- ~i +
- 6\ ~ (AD) = ~[======] ~i + ~[======] ~j + ~[======] ~k
- VALUES
- \ ~ (AD) =
- ~i +
- =\We multiply the unit vector along AD by the unknown tension
- 3T(AD) to obtain the force exerted by AD on point A:
- \ ~F(AD) =
- T(AD) ~i +
- T(AD) ~j
- T(AD) ~k
- ~F(AD) =
- T(AD)~i +
- T(AD)~j
- T(AD)~k
- ~W = (-60 lb) ~j
- RWe now draw the free-body diagram of point A, showing the four forces acting on A.
- 60 lb
- ~M\Since particle A is in equilibrium, the sum of the components of the forces
- c~+acting on A must be zero in any direction:
- ~Fx = 0: -0.490 T(AB) - 0.289 T(AC)
- T(AD) = 0
- ~Fy = 0: 0.816 T(AB) + 0.889 T(AC)
- T(AD) - 60 lb = 0
- ~Fz = 0: (~[======] ) T(AB) + (~[======] ) T(AC) + (~[======] ) T(AD) = 0
- COEFFICIENTS
- ~Fx = 0: -0.490 T(AB) - 0.289 T(AC)
- T(AD) = 0
- ~Fy = 0: 0.816 T(AB) + 0.889 T(AC)
- T(AD) - 60 lb = 0
- ~Fz = 0: 0.306 T(AB) - 0.356 T(AC)
- T(AD) = 0
- yEWe shall solve the three equations obtained for the unknown tensions.
- k~YAt
- VuE\T(AB) = ~[======] lb T(AC) = ~[======] lb T(AD) = ~[======] lb
- TENSIONS
- T(AB) =
- lb T(AC) =
- lb T(AD) =
- sC\Tension in a cable cannot be negative. The container will not be
- sBin equilibrium for point D as given. Select new coordinates such
- bs+that the triangle BCD contains the origin.
- r2\Since the tensions in cables AB and AC are zero,
- r*only cable AD supports the load; this is
- kr,because D is located directly above point A.
- q7\Since the tension in cable AB is zero, only cables AC
- q2and AD support the load; this is because the line
- q.joining C and D passes directly above point A.
- q7\Since the tension in cable AC is zero, only cables AB
- p2and AD support the load; this is because the line
- p.joining B and D passes directly above point A.
- o4These are the answers you obtained for this example.
- uo!The previous example resulted in:
- T(AB) =
- lb T(AC) =
- lb T(AD) =
- n6\Only the location of D was changed; cables AB and AC
- gnDremained unchanged. Yet, the tension changed _in all three cables_.
- i7\Three forces are applied as shown to a corner plate.
- Qi6The given dimensions are expressed in mm. Select the
- i6magnitude and sense of the forces applied at A and B,
- h:and the magnitude and direction of the force applied at C.
- 50 mm
- 100 mm
- 150 mm
- 40 mm
- f=\The forces may have any value between 0 and 1000 N, and the
- af3angle ~
- may have any value between 0.00 and 360~
- ;jzp=
- /`/\We resolve the forces into X and Y components:
- M_ /sin/cos/
- ~F(A) = (~[======] N)~j`
- ~F(B) = (~[======] N)~i`
- ~F(C) = (
- ) * ~[===] (
- )~i + (
- ) * ~[===] (
- ^%VALUES AND S for SINE or C for COSINE
- 5] ~F(A) = (
- )~j ~F(B) = (
- \ ~F(C) = (
- \ N)~i + (
- N)~j
- \>\We also determine the position vectors of points A, B, and C:
- meters
- zXYIt
- &[2 ~r(A) = (~[========] m)~i + (~[========] m)~j`
- ~r(B) = (~[========] m)~j`
- Z1 ~r(C) = (~[========] m)~i + (~[========] m)~j
- VALUES
- Y"~r(A) = (-0.050 m)~i + (0.040 m)~j
- ~r(B) = (-0.100 m)~j
- 7Y"~r(C) = ( 0.150 m)~i + (0.040 m)~j
- XBWe now reduce the given system of forces to a force-couple system
- XCconsisting of a force ~R attached at ~O and a couple of moment ~M.
- QX5The force ~R is obtained by adding the given forces:
- X-~R = ~F(A) + ~F(B) + ~F(C)
- WJ~ = (~[======] N)~j + (~[======] N)~i + (~[======] N)~i + (~[======] N)~j
- VALUES
- SV1We factor the unit vectors ~i and ~j and obtain:
- V&~R = (~[======] N)~i + (~[======] N)~j
- VALUES
- U]The moment ~M of the couple is obtained by adding the moments about ~O of the various forces:
- T:& ~M = ~r(A) ~x ~F(A) + ~r(B) ~x ~F(B) + ~r(C) ~x ~F(C)
- ST:&We shall compute each vector product separately from the
- T1expressions obtained above, keeping in mind that:
- SB& ~i ~x ~i = 0 ~i ~x ~j = ~k ~j ~x ~i = -~k ~j ~x ~j = 0
- ZS!The first term is ~r(A) ~x ~F(A):
- 'SH\~r(A) ~x ~F(A) = [(~[======] m)~i + (~[======] m)~j] ~x (~[======] N)~j
- meters
- 1Z|p=
- meters
- VALUES
- Q#\~ ~ ~ = (-0.050 m)~i ~x (
- Q$\~ ~ ~ = (~[======] N~
- VALUE
- P"The second term is ~r(B) ~x ~F(B):
- P4\~r(B) ~x ~F(B) = (~[======] m)~j ~x (~[======] N)~i
- meters
- VALUES
- O#~ ~ ~ = (~[======] N~
- VALUE
- N!The third term is ~r(C) ~x ~F(C):
- NV&~r(C) ~x ~F(C) = [(~[=====] m)~i+(~[=====] m)~j] ~x [(~[======] N)~i+(~[======] N)~j]
- meters
- meters
- VALUES
- L&&~ ~ ~ = 0 + (0.150 m)~i ~x (
- N)~j + (0.040 m)~j ~x (
- L N)~i + 0
- L9&~ ~ ~ = (~[======] N~
- m)~k + (~[======] N~
- 1S|p=
- VALUES
- J$&~ ~ ~ = (~[======] N~
- VALUE
- Thus we have the following:
- & ~r(A) ~x ~F(A) = (
- ~r(B) ~x ~F(B) = (
- ~r(C) ~x ~F(C) = (
- H$&and the sum of these terms gives ~M
- H$&~ ~ ~M = (~[======] N~
- THE SUM
- XG>Thus the force-couple system equivalent to the given forces is
- &~R = (
- N)~i+ (
- N)~j
- ~M = (
- &In magnitude-direction form,
- &~R =
- ~M = (
- @8&Since ~R = 0 and ~M = 0, the given system of forces is
- @:equivalent to zero. The corner plate is in _equilibrium_.
- @2\Since ~M = 0, the given system of forces reduces
- ?,to a single force attached at the origin ~O.
- D?*\Since ~R = 0, the given system of forces
- ?(reduces to a single couple which may be
- applied anywhere on the body.
- ~R = (
- N)~i+ (
- N)~j
- ~ =
- ~M = (
- =5Since the resultant ~R is parallel to the x-axis, it
- will not intersect that axis.
- <J\To obtain the point where the single resultant ~R intersects the x-axis,
- ^<@we move both components of ~R along the x-axis until the moment
- <+of the y component about ~O is equal to ~M.
- S:.\(x)~i ~x (~[======] N)~j = (~[======] N~
- VALUES
- (x) (
- O9 N)~k = (
- 9$&We shall solve this equation for x.
- &x = ~[=======] x 10^-3 m
- ANSWER
- &x =
- x 10^-3 m
- 67 mm (off range - intercept cannot be shown on diagram)
- X-intercept =
- 56\Since the resultant ~R is parallel to the y-axis, it
- will not intersect that axis.
- 5>\To obtain the point where the single resultant ~R intersects
- 4Athe y-axis, we move both components of ~R along the y-axis until
- 46the moment of the x component about ~O is equal to ~M.
- 2.\(y)~j ~x (~[======] N)~i = (~[======] N~
- VALUES
- -(y) (
- 1 N)~k = (
- g1$&We shall solve this equation for y.
- &y = ~[=======] x 10^-3 m
- ANSWER
- &y =
- x 10^-3 m
- N/7 mm (off range - intercept cannot be shown on diagram)
- Y-intercept =
- SETUPJUMPTABLE FOLLOWS
- FARCALLHANDLER FOLLOWS
-