ASVAB Mechanical Comprehension Practice Test 386021 Results

Your Results Global Average
Questions 5 5
Correct 0 3.30
Score 0% 66%

Review

1

An inclined plane increases ___________ to reduce ____________.

58% Answer Correctly

force, distance

distance, force

force, power

distance, power


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

When it comes to force, mass and acceleration have what kind of relationship?

66% Answer Correctly

exponential

linear

inverse

logarithmic


Solution

Newton's Second Law of Motion states that "The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object." This Law describes the linear relationship between mass and acceleration when it comes to force and leads to the formula F = ma or force equals mass multiplied by rate of acceleration.


3

Drag is a type of:

81% Answer Correctly

kinetic energy

friction

potential energy

work


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

Torque involves a perpendicular force applied to a lever arm that moves around a center of rotation. Increasing the length of the lever arm will do which of the following?

54% Answer Correctly

increase applied force

decrease torque

increase torque

decrease applied force


Solution

Torque measures force applied during rotation: τ = rF.  Torque (τ, the Greek letter tau) = the radius of the lever arm (r) multiplied by the force (F) applied. Radius is measured from the center of rotation or fulcrum to the point at which the perpendicular force is being applied. The resulting unit for torque is newton-meter (N-m) or foot-pound (ft-lb).


5 If you lift a 5 lbs. rock 33 ft. from the ground, how much work have you done?
70% Answer Correctly
38 ft⋅lb
330 ft⋅lb
165 ft⋅lb
None of these is correct

Solution
Work is force times distance. In this case, the force is the weight of the rock so:
\( W = F \times d \)
\( W = 5 \times 33 \)
\( W = 165 \)