ASVAB Mechanical Comprehension Practice Test 246900 Results

Your Results Global Average
Questions 5 5
Correct 0 3.33
Score 0% 67%

Review

1

The mass of an object correlates to the size of the object but ultimately depends on:

67% Answer Correctly

the object's density

the object's weight

gravity

the object's potential energy


Solution

Mass is a measure of the amount of matter in an object.  In general, larger objects have larger mass than smaller objects but mass ultimately depends on how compact (dense) a substance is.


2

On Earth, acceleration due to gravity (g) is approximately __________. 

81% Answer Correctly

1 m/s

1 m/s2

9.8 m/s2

6.67 x 10-11 m/s2


Solution

Newton's Law of Univeral Gravitation defines the general formula for the attraction of gravity between two objects:  \(\vec{F_{g}} = { Gm_{1}m_{2} \over r^2}\) . In the specific case of an object falling toward Earth, the acceleration due to gravity (g) is approximately 9.8 m/s2


3

Which of the following statements about drag is false?

58% Answer Correctly

the amount of drag depends on the speed of an object

drag occurs during movement through a fluid

slower objects experience more drag than faster objects

the amount of drag depends on the shape of an object


Solution

Drag is friction that opposes movement through a fluid like liquid or air. The amount of drag depends on the shape and speed of the object with slower objects experiencing less drag than faster objects and more aerodynamic objects experiencing less drag than those with a large leading surface area.


4 If a 55 lbs. weight is placed 1 ft. from the fulcrum at the blue arrow and the green box is 8 ft. from the fulcrum, how much would the green box have to weigh to balance the lever?
61% Answer Correctly
20.63 lbs.
6.88 lbs.
2.29 lbs.
3.44 lbs.

Solution

To balance this lever the torques on each side of the fulcrum must be equal. Torque is weight x distance from the fulcrum so the equation for equilibrium is:

Rada = Rbdb

where a represents the left side of the fulcrum and b the right, R is resistance (weight) and d is the distance from the fulcrum.

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

Ra = \( \frac{R_bd_b}{d_a} \) = \( \frac{55 lbs. \times 1 ft.}{8 ft.} \) = \( \frac{55 ft⋅lb}{8 ft.} \) = 6.88 lbs.


5

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

all of these are correct

the portions of the system at an altitude below the input

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.