ASVAB Mechanical Comprehension Practice Test 712538 Results

Your Results Global Average
Questions 5 5
Correct 0 2.88
Score 0% 58%

Review

1

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

decrease torque

increase applied force

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).


2

Drag is a type of:

82% Answer Correctly

friction

potential energy

work

kinetic energy


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.


3

Which of the following represents the force a surface exerts when an object presses against it?

48% Answer Correctly

friction

normal force

mass

counter force


Solution

Normal force (FN) represents the force a surface exerts when an object presses against it.


4

Lisa lifts a 25 pound box from the floor onto a loading dock 4 ft. off the ground. Sam slides the same box along a ramp to move it up another 4 ft. onto a flatbed truck. Who has done more work?

50% Answer Correctly

They have done an equal amount of work

Neither have done any work

Sam

Lisa


Solution

Work is force multiplied by distance. Because both Connie and Sam moved the same weight the same distance they have done an equal amount of work. Sam employed the mechnacial advantage of an inclined plane so he exerted less effort to do the work but the amount of work done was still the same.


5

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

56% Answer Correctly

mechanical advantage

efficiency

force multiplication

power


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.