ASVAB Mechanical Comprehension Practice Test 739554 Results

Your Results Global Average
Questions 5 5
Correct 0 3.26
Score 0% 65%

Review

1

A box is resting on a smooth floor. Static friction is present:

59% Answer Correctly

only if normal force is present

at all times

if the coefficient of friction is greater than one

when an attempt is made to move the box
Solution

For any given surface, the coefficient of static friction is higher than the coefficient of kinetic friction. More force is required to initally get an object moving than is required to keep it moving. Additionally, static friction only arises in response to an attempt to move an object (overcome the normal force between it and the surface).

2

Which of these is the formula for force?

77% Answer Correctly

F = am2

F = m/a

F = ma

F = a/m
Solution

Newton's Second Law of Motion states that "The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object." This Law describes the linear relationship between mass and acceleration when it comes to force and leads to the formula F = ma or force equals mass multiplied by rate of acceleration.

3 If you have a gear train with three gears, the first with 22 teeth, the second with 14 teeth, and the third with 4 teeth, what is its mechanical advantage?
51% Answer Correctly
11.5
16.5
5.5
8.3
Solution

The mechanical advantage of a gear train is its gear ratio. The gear ratio (Vr) is the product of the gear ratios between the pairs of meshed gears. Let N represent the number of teeth for each gear:

Vr = \( \frac{N_1}{N_2} \) \( \frac{N_2}{N_3} \) \( \frac{N_3}{N_4} \) ... \( \frac{N_n}{N_{n+1}} \)

In this problem, we have three gears so the equation becomes:

Vr = \( \frac{N_1}{N_2} \) \( \frac{N_2}{N_3} \) = \( \frac{22}{14} \) \( \frac{14}{4} \) = \( \frac{22}{4} \) = 5.5

4

When it comes to force, mass and acceleration have what kind of relationship?

66% Answer Correctly

exponential

linear

inverse

logarithmic
Solution

Newton's Second Law of Motion states that "The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object." This Law describes the linear relationship between mass and acceleration when it comes to force and leads to the formula F = ma or force equals mass multiplied by rate of acceleration.

5

What type of load is sudden and for a relatively short duration?

69% Answer Correctly

dynamic load

concentrated load

non-uniformly distributed 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.