1–67.
1–68.
1-69.
0
If a force of 133 pounds is
actually required to move the crate
up the inclined plane, the amount
of force expended in overcoming
friction is
1.
20 lb
2.
33 lb
3.
58 lb
4.
66 lb
Since a force of 133 pounds was
exerted in moving the crate up the
inclined plane, the actual
mechanical advantage is
1.
1/3
2.
2 1/3
3.
3
4.
4
A 3,000–pound automobile is towed
up a ramp 150 feet long running
from the street floor to the second
floor of a garage. The towing
force required was 300 pounds.
What is the distance between floors
if 20 pounds of force were needed
to overcome frictional resistance?
1.
8.6 ft
2. 10 ft
3. 14 ft
4. 15 ft
Information for questions 1–70 and
1–71:
By exerting an effort of 115
pounds, you move a 300–pound crate up an
inclined plane 12 feet long to a truck bed
three feet above the sidewalk.
1–70.
What is the theoretical mechanical
advantage of the inclined plane?
1.
One
2.
Two
3.
Three
4.
Four
1–71.
How much of your effort is used to
overcome friction?
1.
35 lb
2.
40 lb
3.
75 lb
4.
115 lb
1–72.
What is the characteristic shape of
wedges which have a high mechanical
advantage?
1.
Short and thick
2.
Long and thin
3.
Long and thick
4.
Short and thin
1–73.
If a wedge is 6 inches long, 3
inches wide, and 1 1/2 inches thick
at the top, the theoretical
mechanical advantage is
1.
1 1/2
2.
2
3.
3
4.
4
1–74.
A member of a damage control party
uses a maul to drive a wedge in
behind a shore to tighten up a
damaged bulkhead.
The wedge is 15
inches long and 3 inches thick at
the butt.
How many pounds of force
will be delivered against the face
of the wedge by an 80–pound blow on
the wedge butt with the maul?
1.
80 lb
2.
240 lb
3.
400 lb
4.
1,200 lb
1-75.
A 60–pound blow delivered against
the 3/4–inch–thick butt end of a
wedge results in an effective
splitting force of 480 pounds.
How
long is the wedge?
1.
3 in
2.
4 in
3.
6 in
4.
8 in
11
