ASVAB Mechanical Comprehension Practice Test 818178 Results

	Your Results	Global Average
Questions	5	5
Correct	0	3.64
Score	0%	73%

Review

Which of the following is not a characteristic of a ceramic?

61% Answer Correctly

	chemically stable
	high melting point
	low density
	low corrosive action

Solution

Ceramics are mixtures of metallic and nonmetallic elements that withstand exteme thermal, chemical, and pressure environments. They have a high melting point, low corrosive action, and are chemically stable. Examples include rock, sand, clay, glass, brick, and porcelain.

A fixed pulley has a mechanical advantage of:

68% Answer Correctly

	-1
	0
	2
	1

Solution

A fixed pulley is used to change the direction of a force and does not multiply the force applied. As such, it has a mechanical advantage of one. The benefit of a fixed pulley is that it can allow the force to be applied at a more convenient angle, for example, pulling downward or horizontally to lift an object instead of upward.

Which of these is the formula for force?

76% Answer Correctly

	F = ma
	F = m/a
	F = am²
	F = a/m

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.

4 If input effort is 800 ft⋅lb, what output effort will be produced by a machine with a mechanical advantage of 6?

79% Answer Correctly

	4800 ft⋅lb
	0ft⋅lb
	2400ft⋅lb
	19200ft⋅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 800 ft⋅lb by 6 to produce an output effort of 4800 ft⋅lb.

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

80% Answer Correctly

	power
	work
	efficiency
	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.