ASVAB Mechanical Comprehension Practice Test 615438 Results

Your Results Global Average
Questions 5 5
Correct 0 3.13
Score 0% 63%

Review

1

Which of the following surfaces would have the lowest coefficient of friction?

86% Answer Correctly

ice

leather

concrete

tile
Solution

Coefficient of friction (μ) represents how much two materials resist sliding across each other.  Smooth surfaces like ice have low coefficients of friction while rough surfaces like concrete have high μ.

2

Lisa lifts a 25 pound box from the floor onto a loading dock 4 ft. off the ground. Sam slides the same box along a ramp to move it up another 4 ft. onto a flatbed truck. Who has done more work?

50% Answer Correctly

Neither have done any work

Sam

They have done an equal amount of work

Lisa
Solution

Work is force multiplied by distance. Because both Connie and Sam moved the same weight the same distance they have done an equal amount of work. Sam employed the mechnacial advantage of an inclined plane so he exerted less effort to do the work but the amount of work done was still the same.

3

What is work?

60% Answer Correctly

The movement of an object by a force

Force per unit time

Force per unit distance

The potential for exertion
Solution

Work is accomplished when force is applied to an object: W = Fd where F is force in newtons (N) and d is distance in meters (m). Thus, the more force that must be applied to move an object, the more work is done and the farther an object is moved by exerting force, the more work is done. By definition, work is the displacement of an object resulting from applied force.

4

According to Boyle's law, for a fixed amount of gas kept at a fixed temperature, which of the following are inversely proportional?

63% Answer Correctly

volume, mass

pressure, density

density, volume

pressure, volume
Solution

Boyle's law states that "for a fixed amount of an ideal gas kept at a fixed temperature, pressure and volume are inversely proportional".

5 How much work can a 3 hp engine do in 9 seconds?
52% Answer Correctly
6 ft⋅lb
1 ft⋅lb
0 ft⋅lb
14850 ft⋅lb
Solution
Horsepower (hp) is a common measure of power output for complex machines. By definition, a 1 hp machine does 550 ft⋅lb of work in 1 second: 1 hp = 550 ft⋅lb/s. Substituting the variables for this problem gives us:
\( W = 3 hp \times 550 \frac{ft⋅lb}{s} \times 9s = 14850 ft⋅lb \)