ASVAB Mechanical Comprehension Practice Test 899067 Results

	Your Results	Global Average
Questions	5	5
Correct	0	3.32
Score	0%	66%

Review

1 10 lbs. of effort is used by a machine to lift a 20 lbs. box. What is the mechanical advantage of the machine?

84% Answer Correctly

	2.2
	6
	2
	1

Solution

Mechanical advantage is resistance force divided by effort force:

MA = \( \frac{F_r}{F_e} \) = \( \frac{20 lbs.}{10 lbs.} \) = 2

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
	energy
	rotational direction
	force

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.

Which of the following is not a type of simple machine?

58% Answer Correctly

	lever
	gear
	screw
	pulley

Solution

The six types of simple machines are the lever, wheel and axle, pulley, inclined plane, wedge, and screw.

The mechanical advantage of a block and tackle is equal to which of the following?

69% Answer Correctly

	the number of connecting ropes
	the number of pulleys
	the number of loads
	the number of input forces

Solution

Two or more pulleys used together constitute a block and tackle which, unlike a fixed pulley, does impart mechanical advantage as a function of the number of pulleys that make up the arrangement. So, for example, a block and tackle with three pulleys would have a mechanical advantage of three.

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

57% Answer Correctly

	parallel to
	perpendicular to
	along
	opposite 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.