ASVAB Mechanical Comprehension Practice Test 378066 Results

Your Results Global Average
Questions 5 5
Correct 0 3.24
Score 0% 65%

Review

1

An object's resistance to changes in direction is known as:

82% Answer Correctly

mass

kinetic energy

inertia

weight
Solution

The more mass a substance has the more force is required to move it or to change its direction. This resistance to changes in direction is known as inertia.

2

The measure of how much of the power put into a machine is turned into movement or force is called:

56% Answer Correctly

force multiplication

power

efficiency

mechanical advantage
Solution

The efficiency of a machine describes how much of the power put into the machine is turned into movement or force. A 100% efficient machine would turn all of the input power into output movement or force. However, no machine is 100% efficient due to friction, heat, wear and other imperfections that consume input power without delivering any output.

3

The advantage of using a third-class lever is that it increases:

37% Answer Correctly

the speed of the load

the force applied to the load

the distance traveled by the load

the mechanical advantage of the lever
Solution

A third-class lever is used to increase distance traveled by an object in the same direction as the force applied. The fulcrum is at one end of the lever, the object at the other, and the force is applied between them. This lever does not impart a mechanical advantage as the effort force must be greater than the load but does impart extra speed to the load. Examples of third-class levers are shovels and tweezers.

4

The work done by the sum of all forces acting on a particle equals the change in the kinetic energy of the particle. This defines which of the following?

60% Answer Correctly

conservation of mechanical energy

work-energy theorem

Pascal's law

mechanical advantage
Solution

The work-energy theorem states that the work done by the sum of all forces acting on a particle equals the change in the kinetic energy of the particle. Simply put, work imparts kinetic energy to the matter upon which the work is being done.

5 What is the mechanical advantage of this inclined plane if the length of the ramp is 24 ft. and the height of the green box is 4 ft.?
82% Answer Correctly
1
2
8
6
Solution

The mechanical advantage (MA) of an inclined plane is the effort distance divided by the resistance distance. In this case, the effort distance is the length of the ramp and the resistance distance is the height of the green box:

MA = \( \frac{d_e}{d_r} \) = \( \frac{24 ft.}{4 ft.} \) = 6