ASVAB Mechanical Comprehension Practice Test 640283 Results

Your Results Global Average
Questions 5 5
Correct 0 3.21
Score 0% 64%

Review

1

Potential energy is energy that has the potential to be converted into what?

81% Answer Correctly

work

heat

 kinetic energy

power
Solution

Potential energy is the energy of an object by virtue of its position relative to other objects. It is energy that has the potential to be converted into kinetic energy.

2 If the handles of a wheelbarrow are 2.5 ft. from the wheel axle and the load is concentrated at a point 1.0 ft. from the axle, how many pounds of load will a 140 lbs. force lift?
47% Answer Correctly
350
80
3.4
None of these is correct
Solution
This problem describes a second-class lever and, for a second class lever, the effort force multiplied by the effort distance equals the resistance force multipied by the resistance distance: Fede = Frdr. In this problem we're looking for resistance force:
\( F_r = \frac{F_e d_e}{d_r} \)
\( F_r = \frac{140 \times 2.5}{1.0} \)
\( F_r = \frac{350.0}{1.0} \)
\( F_r = 350 \)
3 A = 4 ft., the green box weighs 50 lbs., and the blue box weighs 70 lbs. What does distance B need to be for this lever to balance?
65% Answer Correctly
280 ft.
200 ft.
8.57 ft.
2.86 ft.
Solution
In order for this lever to balance, the torque acting on side A must equal the torque acting on side B. Torque is weight x distance from the fulcrum which means that the following must be true for the lever to balance:

fAdA = fBdB

For this problem, the equation becomes:

50 lbs. x 4 ft. = 70 lbs. x dB

dB = \( \frac{50 \times 4 ft⋅lb}{70 lbs.} \) = \( \frac{200 ft⋅lb}{70 lbs.} \) = 2.86 ft.

4

The mass of an object correlates to the size of the object but ultimately depends on:

67% Answer Correctly

the object's density

gravity

the object's potential energy

the object's weight
Solution

Mass is a measure of the amount of matter in an object.  In general, larger objects have larger mass than smaller objects but mass ultimately depends on how compact (dense) a substance is.

5

For a hydraulic system, pressure applied to the input of the system will increase the pressure in which parts of the system?

58% Answer Correctly

the portions of the system at an altitude below the input

the portions of the system at an altitude above the input

all of these are correct

everywhere in the system
Solution

Pascal's law states that a pressure change occurring anywhere in a confined incompressible fluid is transmitted throughout the fluid such that the same change occurs everywhere. For a hydraulic system, this means that a pressure applied to the input of the system will increase the pressure everywhere in the system.