2-73.
An annunition hoist is powered by a
2-hp motor.
Working at full load,
how long does it take the motor to
raise a 50–pound shell 22 feet from
the handling room to the gun
turret?
1.
1/2
sec
2.
1
sec
3.
1 1/2 sec
4.
2
sec
2–74.
If it is desired to develop ten
usable horsepower from an engine
which is 50 percent efficient, the
engine must have a minimum rated
horsepower of at least
1.
10
2.
20
3.
100
4.
150
2–75.
What information is sufficient to
find the horsepower rating of a
motor by means of the Prony brake
in figure 8–3 of the textbook?
1.
The readings on both scales,
the radius of the pulley, and
the time it takes the motor to
reach maximum speed
2.
Tile readings on both scales.
the radius of the pulley, and
the speed of the motor
3.
The readings on both scales,
the radius of the pulley, and
the diameter of the motor shaft.
4.
The radius of the pulley and
the readings on the scales when
the belt is pulled tight enough
to prevent the motor from
turning
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