ASVAB Mechanical Comprehension Practice Test 152906 Results

Your Results Global Average
Questions 5 5
Correct 0 2.95
Score 0% 59%

Review

1

For a hydraulic system, pressure applied to the input of the system will increase the pressure in which parts of the system?

58% Answer Correctly

the portions of the system at an altitude below the input

all of these are correct

the portions of the system at an altitude above the input

everywhere in the system


Solution

Pascal's law states that a pressure change occurring anywhere in a confined incompressible fluid is transmitted throughout the fluid such that the same change occurs everywhere. For a hydraulic system, this means that a pressure applied to the input of the system will increase the pressure everywhere in the system.


2

Collinear forces:

72% Answer Correctly

act in a common plane

pass through a common point

are unrelated to each other

act along the same line of action


Solution

Collinear forces act along the same line of action, concurrent forces pass through a common point and coplanar forces act in a common plane.


3 If the radius of the axle is 7 and the radius of the wheel is 12, what is the mechanical advantage of this wheel and axle configuration?
52% Answer Correctly
1.71
12
7
0.58

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 12 and the output radius (where the resistance is being applied) is 7 for a mechanical advantage of \( \frac{12}{7} \) = 1.71


4

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

tension is equal in all parts of the rope

near the car

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.


5

Power is the rate at which:

62% Answer Correctly

potential energy is converted into kinetic energy

friction is overcome

input force is transferred to output force

work is done


Solution

Power is the rate at which work is done, P = w/t, or work per unit time. The watt (W) is the unit for power and is equal to 1 joule (or newton-meter) per second. Horsepower (hp) is another familiar unit of power used primarily for rating internal combustion engines. 1 hp equals 746 watts.