ASVAB Mechanical Comprehension Practice Test 43228 Results

	Your Results	Global Average
Questions	5	5
Correct	0	3.11
Score	0%	62%

Review

The mechanical advantage of a wheel and axle is equal to the:

61% Answer Correctly

	difference in the diameters of the wheels
	ratio of the diameters of the wheels
	difference in the lengths of the axles
	length of the axle

Solution

A wheel and axle uses two different diameter wheels mounted to a connecting axle. Force is applied to the larger wheel and large movements of this wheel result in small movements in the smaller wheel. Because a larger movement distance is being translated to a smaller distance, force is increased with a mechanical advantage equal to the ratio of the diameters of the wheels. An example of a wheel and axle is the steering wheel of a car.

2 If you lift a 19 lbs. rock 18 ft. from the ground, how much work have you done?

71% Answer Correctly

	342 ft⋅lb
	162 ft⋅lb
	684 ft⋅lb
	1 ft⋅lb

Solution

Work is force times distance. In this case, the force is the weight of the rock so:
\( W = F \times d \)
\( W = 19 \times 18 \)
\( W = 342 \)

The principle of conservation of mechanical energy states that, as long as no other forces are applied, what will remain constant as an object falls?

45% Answer Correctly

	acceleration
	potential energy
	kinetic energy
	total mechanical energy

Solution

As an object falls, its potential energy is converted into kinetic energy. The principle of conservation of mechanical energy states that, as long as no other forces are applied, total mechanical energy (PE + KE) of the object will remain constant at all points in its descent.

Which of these is the formula for force?

77% Answer Correctly

	F = a/m
	F = am²
	F = m/a
	F = ma

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.

The principle of moments defines equilibrium in terms of:

53% Answer Correctly

	torque
	power
	energy
	speed

Solution

According to the principle of moments, you can maintain equilibrium if the moments (forces) tending to clockwise rotation are equal to the moments tending to counterclockwise rotation. Another name for these moments of force is torque.