1-35.
In the arrangement of figure 1K the
purpose of block A is to
1.
increase the mechanical
advantage of the block
2.
change the direction of the
applied force
3.
hold up block B
4.
act as a runner for block B
136.
A luff tackle is a block and tackle
consisting of a
1-38.
For which requirement will it be to
your advantage to rig a yard to a
stay tackle if each tackle has a
theoretical mechanical advantage of
two?
1.
A theoretical mechanical
advantage of 4
2.
A change in the direction of
pull for convenience
3.
A heavy crate to be lifted to
the other side of a low fence
4.
An increase in speed
1.
fixed double block and a
movable single block
2.
movable double block and a
fixed single block
3.
fixed single block and a
movable single block
4.
fixed triple block and a
139.
The overall mechanical advantage in
movable double block
figure 1L is about
Information for questions 1-37 and
o
138:
Alone youre going to hoist
a 600pound load to a height of 36 feet.
You can pull 160 pounds worth.
You have
to use a fixed block fastened to a beam
above you.
You have a movable block
attached to the pad eye of the load.
137.
What minimum mechanical advantage
must the block and tackle provide?
1.
One
2.
Two
3.
Three
4.
Four
1.
five
2.
six
3.
eight
4.
twelve
1-40.
You are using a differential pulley
to lift a load of 2,400 pounds.
Fifty pounds of effort are required
to overcome the frictional
resistance of the pulley.
What
force is necessary to lift the load
if the theoretical mechanical
advantage of the pulley is 24?
1.
50 lb
2.
100 lb
3.
150 lb
4.
200 lb
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