ASVAB Mechanical Comprehension Practice Test 981769 Results

Your Results Global Average
Questions 5 5
Correct 0 3.54
Score 0% 71%

Review

1 What is the mechanical advantage of this inclined plane if the length of the ramp is 24 ft. and the height of the green box is 3 ft.?
82% Answer Correctly
7.2
17
24
8

Solution

The mechanical advantage (MA) of an inclined plane is the effort distance divided by the resistance distance. In this case, the effort distance is the length of the ramp and the resistance distance is the height of the green box:

MA = \( \frac{d_e}{d_r} \) = \( \frac{24 ft.}{3 ft.} \) = 8


2

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

85% Answer Correctly

concrete

tile

leather

ice


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.


3

On Earth, acceleration due to gravity (g) is approximately __________. 

81% Answer Correctly

1 m/s2

6.67 x 10-11 m/s2

1 m/s

9.8 m/s2


Solution

Newton's Law of Univeral Gravitation defines the general formula for the attraction of gravity between two objects:  \(\vec{F_{g}} = { Gm_{1}m_{2} \over r^2}\) . In the specific case of an object falling toward Earth, the acceleration due to gravity (g) is approximately 9.8 m/s2


4 If the radius of the axle is 3 and the radius of the wheel is 8, what is the mechanical advantage of this wheel and axle configuration?
41% Answer Correctly
8
5
2.67
0.38

Solution

The mechanical advantage of a wheel and axle is the input radius divided by the output radius:

MA = \( \frac{r_i}{r_o} \)

In this case, the input radius (where the effort force is being applied) is 3 and the output radius (where the resistance is being applied) is 8 for a mechanical advantage of \( \frac{3}{8} \) = 0.38


5

What type of load doesn't create specific stress points or vary with time?

60% Answer Correctly

static uniformly distributed load

non-uniformly distributed load

concentrated load

impact load


Solution

A concentrated load acts on a relatively small area of a structure, a static uniformly distributed load doesn't create specific stress points or vary with time, a dynamic load varies with time or affects a structure that experiences a high degree of movement, an impact load is sudden and for a relatively short duration and a non-uniformly distributed load creates different stresses at different locations on a structure.