ASVAB Mechanical Comprehension Practice Test 626560 Results

	Your Results	Global Average
Questions	5	5
Correct	0	3.20
Score	0%	64%

Review

1 If input effort is 300 ft⋅lb, what output effort will be produced by a machine with a mechanical advantage of 9?

79% Answer Correctly

	5400ft⋅lb
	1350ft⋅lb
	2700 ft⋅lb
	10800ft⋅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 9 will multiply an input effort of 300 ft⋅lb by 9 to produce an output effort of 2700 ft⋅lb.

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.

The mechanical advantage of a wheel and axle is equal to the:

60% Answer Correctly

	difference in the diameters of the wheels
	length of the axle
	difference in the lengths of the axles
	ratio of the diameters of the wheels

Solution

A wheel and axle uses two different diameter wheels mounted to a connecting axle. Force is applied to the larger wheel and large movements of this wheel result in small movements in the smaller wheel. Because a larger movement distance is being translated to a smaller distance, force is increased with a mechanical advantage equal to the ratio of the diameters of the wheels. An example of a wheel and axle is the steering wheel of a car.

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

57% Answer Correctly

	mechanics
	engineering
	aeronautics
	physics

Solution

Mechanics deals with motion and the forces that produce motion.

A box is resting on a smooth floor. Static friction is present:

59% Answer Correctly

	at all times
	only if normal force is present
	if the coefficient of friction is greater than one
	when an attempt is made to move the box

Solution

For any given surface, the coefficient of static friction is higher than the coefficient of kinetic friction. More force is required to initally get an object moving than is required to keep it moving. Additionally, static friction only arises in response to an attempt to move an object (overcome the normal force between it and the surface).