ASVAB Mechanical Comprehension Practice Test 120886 Results

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

Review

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

66% Answer Correctly

	static load
	concentrated load
	impact load
	dynamic 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.

2 If the green arrow in this diagram represents 500 ft⋅lb of work, how far will the box move if it weighs 250 pounds?

72% Answer Correctly

	500 ft.
	2 ft.
	1 ft.
	1000 ft.

Solution

The Law of Work states that the work put into a machine is equal to the work received from the machine under ideal conditions. In equation form, that's:

W_in = W_out
F_effort x d_effort = F_resistance x d_resistance

In this problem, the effort work is 500 ft⋅lb and the resistance force is 250 lbs. and we need to calculate the resistance distance:

W_in = F_resistance x d_resistance
500 ft⋅lb = 250 lbs. x d_resistance
d_resistance = \( \frac{500ft⋅lb}{250 lbs.} \) = 2 ft.

Sam can do 50 ft. lb. of work in 2 minutes and 5 seconds. What would Sam have to do to increase his power output?

63% Answer Correctly

	do 100 ft. lb. of work in 4 minutes 12 seconds
	do the work in 2 minutes
	do the work in 3 minutes
	do 25 ft. lb. of work in 2 minutes 5 seconds

Solution

Power is the rate of doing work or \(\frac{W}{t}\). To increase power, increase the work being done in the same amount of time or do the same amount of work in less time.

Which of the following is the formula for gravitational potential energy?

61% Answer Correctly

	\(PE = { 1 \over 2} mv^2\)
	\(PE = mg^2h\)
	\(PE = mgh\)
	\(PE = { 1 \over 2} mg^2\)

Solution

Gravitational potential energy is energy by virtue of gravity. The higher an object is raised above a surface the greater the distance it must fall to reach that surface and the more velocity it will build as it falls. For gravitational potential energy, PE = mgh where m is mass (kilograms), h is height (meters), and g is acceleration due to gravity which is a constant (9.8 m/s²).

What type of load is sudden and for a relatively short duration?

69% Answer Correctly

	non-uniformly distributed load
	dynamic load
	concentrated load
	impact load