ASVAB Mechanical Comprehension Practice Test 960594 Results

Your Results Global Average
Questions 5 5
Correct 0 2.99
Score 0% 60%

Review

1

Which of the following is not a type of bridge?

74% Answer Correctly

block

truss

arch

cable
Solution

The six basic bridge forms are beam, truss, arch, cantilever, cable, and suspension.

2

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

59% Answer Correctly

if the coefficient of friction is greater than one

when an attempt is made to move the box

only if normal force is present

at all times
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).

3 If the handles of a wheelbarrow are 1.0 ft. from the wheel axle, how many pounds of force must you exert to lift the handles if it's carrying a 200 lbs. load concentrated at a point 1.5 ft. from the axle?
52% Answer Correctly
0
300
None of these is correct
133.3
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 effort force:
\( F_e = \frac{F_r d_r}{d_e} \)
\( F_e = \frac{200 \times 1.5}{1.0} \)
\( F_e = \frac{300.0}{1.0} \)
\( F_e = 300 \)
4

Which of the following represents how much two materials resist sliding across each other?

53% Answer Correctly

kinetic friction

coefficient of friction

normal friction

static friction
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.

5

Which of the following is not a characteristic of a ceramic?

61% Answer Correctly

chemically stable

low corrosive action

high melting point

low density
Solution

Ceramics are mixtures of metallic and nonmetallic elements that withstand exteme thermal, chemical, and pressure environments. They have a high melting point, low corrosive action, and are chemically stable. Examples include rock, sand, clay, glass, brick, and porcelain.