ASVAB Mechanical Comprehension Practice Test 700679 Results

Your Results Global Average
Questions 5 5
Correct 0 3.36
Score 0% 67%

Review

1

A ramp is an example of which kind of simple machine?

84% Answer Correctly

none of these

inclined plane

first-class lever

wedge


Solution

An inclined plane is a simple machine that reduces the force needed to raise an object to a certain height. Work equals force x distance and, by increasing the distance that the object travels, an inclined plane reduces the force necessary to raise it to a particular height. In this case, the mechanical advantage is to make the task easier. An example of an inclined plane is a ramp.


2

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

66% Answer Correctly

impact load

dynamic load

concentrated 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.


3 If the green box weighs 20 lbs. and 40 lbs. of force is applied 3 ft. from the fulcrum at the blue arrow, how far from the fulcrum would the green box need to be placed to balance the lever?
55% Answer Correctly
2 ft.
18 ft.
24 ft.
6 ft.

Solution

To balance this lever the torques at the green box and the blue arrow must be equal. Torque is weight x distance from the fulcrum so the equation for equilibrium is:

Rada = Rbdb

where a represents the green box and b the blue arrow, R is resistance (weight/force) and d is the distance from the fulcrum.

Solving for da, our missing value, and plugging in our variables yields:

da = \( \frac{R_bd_b}{R_a} \) = \( \frac{40 lbs. \times 3 ft.}{20 lbs.} \) = \( \frac{120 ft⋅lb}{20 lbs.} \) = 6 ft.


4

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

69% Answer Correctly

dynamic load

concentrated load

impact load

non-uniformly distributed 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.


5

According to Boyle's law, for a fixed amount of gas kept at a fixed temperature, which of the following are inversely proportional?

63% Answer Correctly

volume, mass

density, volume

pressure, density

pressure, volume


Solution

Boyle's law states that "for a fixed amount of an ideal gas kept at a fixed temperature, pressure and volume are inversely proportional".