ASVAB Mechanical Comprehension Practice Test 50224 Results

	Your Results	Global Average
Questions	5	5
Correct	0	2.86
Score	0%	57%

Review

1 If A = 9 ft. and the green box weighs 45 lbs. what is the torque acting on the A side of this lever?

75% Answer Correctly

	0 ft⋅lb
	135 ft⋅lb
	5 ft⋅lb
	405 ft⋅lb

Solution

For a lever, torque is weight x distance from the fulcrum which, in this case, is: 45 ft. x 9 lbs. = 405 ft⋅lb

2 What is the power output of a 2 hp engine that's 70% efficient?

40% Answer Correctly

	3080 \( \frac{ft⋅lb}{s} \)
	1540 \( \frac{ft⋅lb}{s} \)
	2310 \( \frac{ft⋅lb}{s} \)
	770 \( \frac{ft⋅lb}{s} \)

Solution

\( Efficiency = \frac{Power_{out}}{Power_{in}} \times 100 \)
Solving for power out: \( P_{o} = \frac{E \times P_{i}}{100} \)
Knowing that 1 hp = 550 \( \frac{ft⋅lb}{s} \), P_i becomes 2 hp x 550 \( \frac{ft⋅lb}{s} \) = 1100 \( \frac{ft⋅lb}{s} \)
\( P_{o} = \frac{E \times P_{i}}{100} = \frac{70 \times 1100 \frac{ft⋅lb}{s}}{100} \) \( = \frac{77000 \frac{ft⋅lb}{s}}{100} \) = 770 \( \frac{ft⋅lb}{s} \)

The mass of an object correlates to the size of the object but ultimately depends on:

66% Answer Correctly

	gravity
	the object's density
	the object's potential energy
	the object's weight

Solution

Mass is a measure of the amount of matter in an object. In general, larger objects have larger mass than smaller objects but mass ultimately depends on how compact (dense) a substance is.

What's the last gear in a gear train called?

38% Answer Correctly

	output gear
	driver gear
	idler gear
	driven gear

Solution

A gear train is two or more gears linked together. Gear trains are designed to increase or reduce the speed or torque outpout of a rotating system or change the direction of its output. The first gear in the chain is called the driver and the last gear in the chain the driven gear with the gears between them called idler gears.

What type of load varies with time or affects a structure that experiences a high degree of movement?

65% Answer Correctly

	static load
	impact load
	concentrated load
	dynamic load

Solution

A concentrated load acts on a relatively small area of a structure, a static uniformly distributed load doesn't create specific stress points or vary with time, a dynamic load varies with time or affects a structure that experiences a high degree of movement, an impact load is sudden and for a relatively short duration and a non-uniformly distributed load creates different stresses at different locations on a structure.