ASVAB Mechanical Comprehension Practice Test 143753 Results

	Your Results	Global Average
Questions	5	5
Correct	0	3.23
Score	0%	65%

Review

1 If the radius of the axle is 5 and the radius of the wheel is 10, what is the mechanical advantage of this wheel and axle configuration?

52% Answer Correctly

	-5
	5
	2.0
	10

Solution

The mechanical advantage of a wheel and axle is the input radius divided by the output radius:

MA = \( \frac{r_i}{r_o} \)

In this case, the input radius (where the effort force is being applied) is 10 and the output radius (where the resistance is being applied) is 5 for a mechanical advantage of \( \frac{10}{5} \) = 2.0

Which of the following is the formula for gravitational potential energy?

62% Answer Correctly

	\(PE = { 1 \over 2} mg^2\)
	\(PE = { 1 \over 2} mv^2\)
	\(PE = mg^2h\)
	\(PE = mgh\)

Solution

Gravitational potential energy is energy by virtue of gravity. The higher an object is raised above a surface the greater the distance it must fall to reach that surface and the more velocity it will build as it falls. For gravitational potential energy, PE = mgh where m is mass (kilograms), h is height (meters), and g is acceleration due to gravity which is a constant (9.8 m/s²).

The force amplification achieved by using a tool, mechanical device or machine system is called:

80% Answer Correctly

	power
	efficiency
	work
	mechanical advantage

Solution

Mechanical advantage is a measure of the force amplification achieved by using a tool, mechanical device or machine system. Such a device utilizes input force and trades off forces against movement to amplify and/or change its direction.

4 If input effort is 100 ft⋅lb, what output effort will be produced by a machine with a mechanical advantage of 6?

79% Answer Correctly

	16ft⋅lb
	1200ft⋅lb
	2400ft⋅lb
	600 ft⋅lb

Solution

Mechanical advantage is the ratio of output force to input force and tells us by how many times a machine multiplies input effort. So, a machine with a mechanical advantage of 6 will multiply an input effort of 100 ft⋅lb by 6 to produce an output effort of 600 ft⋅lb.

Which of the following is not a type of structural load?

49% Answer Correctly

	occupancy load
	wind load
	live load
	dead load

Solution

Dead load is the weight of the building and materials, live load is additional weight due to occupancy or use, snow load is the weight of accumulated snow on a structure and wind load is the force of wind pressures against structure surfaces.