ASVAB Mechanical Comprehension Practice Test 995551 Results

	Your Results	Global Average
Questions	5	5
Correct	0	3.11
Score	0%	62%

Review

If the handles of a wheelbarrow are 3 ft. from the wheel axle, what force must you exert to lift the handles if it's carrying a 270 lb. load concentrated at a point 0.5 ft. from the axle?

56% Answer Correctly

	90 lbs
	45 lbs
	0.83 lbs
	810 lbs

Solution

This problem describes a second-class lever and, for a second class lever, the effort force multiplied by the effort distance equals the resistance force multipied by the resistance distance: F_ed_e = F_rd_r. Plugging in the variables from this problem yields:

F_e x 3 ft. = 270 lbs x 0.5 ft
F_e = 135 ft-lb. / 3 ft
F_e= 45 lbs

Coplanar forces:

61% Answer Correctly

	pass through a common point
	act in a common plane
	have opposite dimensions
	act along the same line of action

Solution

Collinear forces act along the same line of action, concurrent forces pass through a common point and coplanar forces act in a common plane.

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

66% Answer Correctly

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

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.

Assuming force applied remains constant, which of the following will result in more work being done?

53% Answer Correctly

	moving the object farther
	increasing the coefficient of friction
	moving the object with more acceleration
	moving the object with more speed

Solution

Work is accomplished when force is applied to an object: W = Fd where F is force in newtons (N) and d is distance in meters (m). Thus, the more force that must be applied to move an object, the more work is done and the farther an object is moved by exerting force, the more work is done.

Collinear forces:

72% Answer Correctly

	act in a common plane
	pass through a common point
	act along the same line of action
	are unrelated to each other

Solution

Collinear forces act along the same line of action, concurrent forces pass through a common point and coplanar forces act in a common plane.