ASVAB Mechanical Comprehension Practice Test 762607 Results

Your Results Global Average
Questions 5 5
Correct 0 2.85
Score 0% 57%

Review

1

A truck is using a rope to pull a car. Tension in the rope is greatest in which of the following places?

50% Answer Correctly

near the car

tension is equal in all parts of the rope

in the middle

near the truck


Solution

Tension is a force that stretches or elongates something. When a cable or rope is used to pull an object, for example, it stretches internally as it accepts the weight that it's moving. Although tension is often treated as applying equally to all parts of a material, it's greater at the places where the material is under the most stress.


2 If the radius of the axle is 3 and the radius of the wheel is 4, what is the mechanical advantage of this wheel and axle configuration?
36% Answer Correctly
0
-1
1
1

Solution

The mechanical advantage of a wheel and axle lies in the difference in radius between the inner (axle) wheel and the outer wheel. But, this mechanical advantage is only realized when the input effort and load are applied to different wheels. Applying both input effort and load to the same wheel results in a mechanical advantage of 1.


3

What type of load varies with time or affects a structure that experiences a high degree of movement?

66% Answer Correctly

concentrated load

dynamic load

impact load

static 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.


4 The radius of the axle is 5, the radius of the wheel is 8, and the blue box weighs 95 lbs. What is the effort force necessary to balance the load?
53% Answer Correctly
8 lbs.
5 lbs.
12.8 lbs.
59.38 lbs.

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 8 and the output radius (where the resistance is being applied) is 5 for a mechanical advantage of \( \frac{8}{5} \) = 1.6

MA = \( \frac{load}{effort} \) so effort = \( \frac{load}{MA} \) = \( \frac{95 lbs.}{1.6} \) = 59.38 lbs.


5 What's the mechanical advantage of a wedge that's 5 inches wide and 35 inches long?
83% Answer Correctly
3
7
10.5
6.3

Solution

The mechanical advantage (MA) of a wedge is its length divided by its thickness:

MA = \( \frac{l}{t} \) = \( \frac{35 in.}{5 in.} \) = 7