ASVAB Mechanical Comprehension Practice Test 22341 Results

Your Results Global Average
Questions 5 5
Correct 0 3.19
Score 0% 64%

Review

1

Which of the following is the formula for hydraulic pressure?

58% Answer Correctly

P = F/A2

P = FA

P = F/A

P = FA2
Solution

Hydraulics is the transmission of force through the use of liquids. Liquids are especially suited for transferring force in complex machines because they compress very little and can occupy very small spaces. Hydraulic pressure is calculated by dividing force by the area over which it is applied: P = F/A where F is force in pounds, A is area in square inches, and the resulting pressure is in pounds per square inch (psi).

2

Hydraulics is the transmission of force through the use of which of the following?

73% Answer Correctly

gear systems

liquids

air pressure

torque
Solution

Hydraulics is the transmission of force through the use of liquids. Liquids are especially suited for transferring force in complex machines because they compress very little and can occupy very small spaces. Hydraulic pressure is calculated by dividing force by the area over which it is applied: P = F/A where F is force in pounds, A is area in square inches, and the resulting pressure is in pounds per square inch (psi).

3 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 210 lbs. force lift?
47% Answer Correctly
84
None of these is correct
0
525
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:
\( F_r = \frac{F_e d_e}{d_r} \)
\( F_r = \frac{210 \times 2.5}{1.0} \)
\( F_r = \frac{525.0}{1.0} \)
\( F_r = 525 \)
4

The mechanical advantage of a wheel and axle is equal to the:

61% Answer Correctly

difference in the lengths of the axles

difference in the diameters of the wheels

length of the axle

ratio of the diameters of the wheels
Solution

A wheel and axle uses two different diameter wheels mounted to a connecting axle. Force is applied to the larger wheel and large movements of this wheel result in small movements in the smaller wheel. Because a larger movement distance is being translated to a smaller distance, force is increased with a mechanical advantage equal to the ratio of the diameters of the wheels. An example of a wheel and axle is the steering wheel of a car.

5 If input effort is 300 ft⋅lb, what output effort will be produced by a machine with a mechanical advantage of 8?
79% Answer Correctly
600ft⋅lb
4800ft⋅lb
0ft⋅lb
2400 ft⋅lb
Solution
Mechanical advantage is the ratio of output force to input force and tells us by how many times a machine multiplies input effort. So, a machine with a mechanical advantage of 8 will multiply an input effort of 300 ft⋅lb by 8 to produce an output effort of 2400 ft⋅lb.