ASVAB Mechanical Comprehension Practice Test 714190 Results

	Your Results	Global Average
Questions	5	5
Correct	0	3.09
Score	0%	62%

Review

Connected gears of different numbers of teeth are used together to change which of the following charasteristics of the input force?

65% Answer Correctly

	torque
	rotational direction
	force
	energy

Solution

Connected gears of different numbers of teeth are used together to change the rotational speed and torque of the input force. If the smaller gear drives the larger gear, the speed of rotation will be reduced and the torque will increase. If the larger gear drives the smaller gear, the speed of rotation will increase and the torque will be reduced.

2 If input effort is 600 ft⋅lb, what output effort will be produced by a machine with a mechanical advantage of 5?

79% Answer Correctly

	3000 ft⋅lb
	750ft⋅lb
	1500ft⋅lb
	120ft⋅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 5 will multiply an input effort of 600 ft⋅lb by 5 to produce an output effort of 3000 ft⋅lb.

A wedge converts force applied to its blunt end into force __________ its inclined surface.

57% Answer Correctly

	perpendicular to
	along
	opposite to
	parallel to

Solution

The wedge is a moving inclined plane that is used to lift, hold, or break apart an object. A wedge converts force applied to its blunt end into force perpendicular to its inclined surface. In contrast to a stationary plane where force is applied to the object being moved, with a wedge the object is stationary and the force is being applied to the plane. Examples of a wedge include knives and chisels.

4 A mass of air has a pressure of 15.0 psi and a volume of 75 ft.³. If the air is compressed to a new volume of 55 ft.³, what is the new pressure?

56% Answer Correctly

	18.4 psi
	40.9 psi
	20.5 psi
	22 psi

Solution

According to Boyle's Law, pressure and volume are inversely proportional:

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

In this problem, V₂ = 55 ft.³, V₁ = 75 ft.³ and P₁ = 15.0 psi. Solving for P₂:

P₂ = \( \frac{P_1}{\frac{V_2}{V_1}} \) = \( \frac{15.0 psi}{\frac{55 ft.^3}{75 ft.^3}} \) = 20.5 psi

The science that deals with motion and the forces that produce motion is called which of the following?

57% Answer Correctly

	mechanics
	physics
	engineering
	aeronautics

Solution

Mechanics deals with motion and the forces that produce motion.