ASVAB Mechanical Comprehension Practice Test 108096 Results

	Your Results	Global Average
Questions	5	5
Correct	0	3.24
Score	0%	65%

Review

A watt is the unit for which of the following?

71% Answer Correctly

	mechanical advantage
	energy
	work
	power

Solution

Power is the rate at which work is done, P = w/t, or work per unit time. The watt (W) is the unit for power and is equal to 1 joule (or newton-meter) per second. Horsepower (hp) is another familiar unit of power used primarily for rating internal combustion engines. 1 hp equals 746 watts.

Which of these is the formula for force?

77% Answer Correctly

	F = a/m
	F = ma
	F = am²
	F = m/a

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.

Which of these will have the most impact on the kinetic energy of an object?

54% Answer Correctly

	its speed
	its direction
	its mass
	its weight

Solution

Kinetic energy is the energy of movement and is a function of the mass of an object and its speed: \(KE = {1 \over 2}mv^2\) where m is mass in kilograms, v is speed in meters per second, and KE is in joules. The most impactful quantity to kinetic energy is velocity as an increase in mass increases KE linearly while an increase in speed increases KE exponentially.

4 How much work can a 1 hp engine do in 10 seconds?

52% Answer Correctly

	0 ft⋅lb
	2 ft⋅lb
	5500 ft⋅lb
	10 ft⋅lb

Solution

Horsepower (hp) is a common measure of power output for complex machines. By definition, a 1 hp machine does 550 ft⋅lb of work in 1 second: 1 hp = 550 ft⋅lb/s. Substituting the variables for this problem gives us:
\( W = 1 hp \times 550 \frac{ft⋅lb}{s} \times 10s = 5500 ft⋅lb \)

What type of load varies with time or affects a structure that experiences a high degree of movement?

66% Answer Correctly

	impact load
	dynamic load
	concentrated load
	static load

Solution

A concentrated load acts on a relatively small area of a structure, a static uniformly distributed load doesn't create specific stress points or vary with time, a dynamic load varies with time or affects a structure that experiences a high degree of movement, an impact load is sudden and for a relatively short duration and a non-uniformly distributed load creates different stresses at different locations on a structure.