ASVAB Mechanical Comprehension Practice Test 493576 Results

	Your Results	Global Average
Questions	5	5
Correct	0	3.31
Score	0%	66%

Review

When it comes to force, mass and acceleration have what kind of relationship?

66% Answer Correctly

	inverse
	linear
	logarithmic
	exponential

Solution

Newton's Second Law of Motion states that "The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object." This Law describes the linear relationship between mass and acceleration when it comes to force and leads to the formula F = ma or force equals mass multiplied by rate of acceleration.

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

57% Answer Correctly

	mechanics
	aeronautics
	physics
	engineering

Solution

Mechanics deals with motion and the forces that produce motion.

The force required to initally get an object moving is __________ the force required to keep it moving.

76% Answer Correctly

	higher than
	the same as
	opposite
	lower than

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).

4 If the handles of a wheelbarrow are 1.5 ft. from the wheel axle and the load is concentrated at a point 0.5 ft. from the axle, how many pounds of load will a 140 lbs. force lift?

47% Answer Correctly

	420
	-7
	None of these is correct
	186.7

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. In this problem we're looking for resistance force:
\( F_r = \frac{F_e d_e}{d_r} \)
\( F_r = \frac{140 \times 1.5}{0.5} \)
\( F_r = \frac{210.0}{0.5} \)
\( F_r = 420 \)

Which of the following surfaces would have the lowest coefficient of friction?

85% Answer Correctly

	concrete
	leather
	ice
	tile

Solution

Coefficient of friction (μ) represents how much two materials resist sliding across each other. Smooth surfaces like ice have low coefficients of friction while rough surfaces like concrete have high μ.