ASVAB Mechanical Comprehension Practice Test 996053 Results

	Your Results	Global Average
Questions	5	5
Correct	0	2.76
Score	0%	55%

Review

1 If you lift a 41 lbs. rock 40 ft. from the ground, how much work have you done?

70% Answer Correctly

	3280 ft⋅lb
	81 ft⋅lb
	1640 ft⋅lb
	800 ft⋅lb

Solution

Work is force times distance. In this case, the force is the weight of the rock so:
\( W = F \times d \)
\( W = 41 \times 40 \)
\( W = 1640 \)

Which of the following statements about drag is false?

58% Answer Correctly

	slower objects experience more drag than faster objects
	the amount of drag depends on the shape of an object
	the amount of drag depends on the speed of an object
	drag occurs during movement through a fluid

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.

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

56% Answer Correctly

	efficiency
	force multiplication
	mechanical advantage
	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.

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

38% Answer Correctly

	driver gear
	idler gear
	driven gear
	output 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.

Boyle's law defines the relationship between pressure and volume as:

57% Answer Correctly

	\(\frac{P_1}{P_2} = \frac{V_1}{V_2}\)
	\({P_1}{P_2} = {V_1}{V_2}\)
	\(\frac{P_1}{P_2} = {V_1}{V_2}\)
	\(\frac{P_1}{P_2} = \frac{V_2}{V_1}\)

Solution

Boyle's law states that "for a fixed amount of an ideal gas kept at a fixed temperature, pressure and volume are inversely proportional". Expressed as a formula, that's \(\frac{P_1}{P_2} = \frac{V_2}{V_1}\)