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This problem set deals with force. See Vector
Addition. |
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| 1. |
An object is acted upon by three forces: 40
lb to the right, 180 lb to the left, and 200 lb to the right. Determine
the resultant force and its direction. |
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F1 = 40 lb
right
F2 = 180 lb left
F3 = 200 lb right |
FR = ? |
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| 2. |
Three forces act upon an object: 50 lb to the
left (180°), 45 lb at 45°, and 60 lb at 280°. Using a metric
ruler and a protractor find the resultant force. |
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F1 = 50 lb @180°
F2 = 45 lb @ 45°
F3 = 60 lb @ 280° |
FR
= ? |
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FR = 28.4 lb @ 254° |
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| 3. |
An object is acted upon by two horizontal forces: 40 lb to the North
and 60 lb to the South.
A. Sketch a "free body" diagram showing the two forces.
B. Find the resultant force, both magnitude and direction.
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F1 = 40 lb North
F2 = 60 lb South |
FR = ? |
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A) 
B) 
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| 4. |
An object is acted on by three forces: Force A is 140 lb to the right,
Force B is 180 lb to the left, and Force C is 200 lb to the right.
A. Sketch a "free body" diagram indicating the forces.
B. Find the resultant force in both magnitude and direction.
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FA = 140 lb right
FB = 180 lb left
FC = 200 lb right |
FR = ? |
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A) 
B) 
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| 5. |
In the laboratory, a force board is set up with three strings pulling
on a center ring. The first pull is 70 newtons at 0° (to the right),
the second pull is 80 newtons at 90°.
| A. |
Draw a "free body" diagram of the ring. |
| B. |
Draw a scaled drawing setting 1 cm = 10 newtons showing
the two forces using the head-to-tail method. Find the third force
by drawing an arrow from the end of the second vector to the beginning
of the first. This is the equilibrant or third vector, since it
has both magnitude and direction. |
| C. |
Add the third vector to the free body diagram. |
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F1 = 70 N at 0°
F2 = 80 N at 90° |
FR = ? |
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A) Free body diagram
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B) Graphical Solution
Feq = 106 N @ 227°
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| 6. |
The values below can be classified as either
scalar (S) or vector (V) quantities. Examine each and identify which it
is. |
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a. 15 N at 30° east of north V
b. 30 °C S
c. 80 kg S
d. 105 mph southwest V
e. 20 lb at 60° V
f. 25 lb/in S
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| 7. |
An object is acted upon by four forces: 10
N at 30°, 8 N at 86°, 15 N at 135°, and 4 N at 290°. |
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| A. |
Sketch the object and forces as a free-body diagram. |
| B. |
Using the graphical head-to-tail method, find the magnitude and
direction of the resultant force. |
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F1 = 10 N at 30°
F2 = 8 N at 86°
F3 = 15 N at 135°
F4 = 4 N at 290°
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FR = ? |
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A) Free Body Diagram
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B) Graphical Solution: FR = 19.8 N @ 89.5°
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| 8. |
An object is acted upon by three forces: 6
lb at 240°, 12 lb at 90°, and 7 lb at 120°. |
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| A. |
Sketch the object and forces as a free-body
diagram. |
| B. |
Using the graphical head-to-tail method,
find the magnitude and direction of the resultant force. |
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F1 = 6 lb at 240°
F2 = 12 lb at 90°
F3 = 7 lb at 120° |
FR = ? |
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A) Free Body Diagram
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B) Graphical Solution
FR = 14.6 lb @ 115°
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