ASVAB Mechanical Comprehension Practice Test 927195 Results

Your Results Global Average
Questions 5 5
Correct 0 3.25
Score 0% 65%

Review

1

A ramp is an example of which kind of simple machine?

84% Answer Correctly

inclined plane

first-class lever

none of these

wedge
Solution

An inclined plane is a simple machine that reduces the force needed to raise an object to a certain height. Work equals force x distance and, by increasing the distance that the object travels, an inclined plane reduces the force necessary to raise it to a particular height. In this case, the mechanical advantage is to make the task easier. An example of an inclined plane is a ramp.

2

Concurrent forces:

55% Answer Correctly

act along the same line of action

act in a common dimension

act in a common plane

pass through a common point
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.

3 If the handles of a wheelbarrow are 0.5 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 210 lbs. force lift?
47% Answer Correctly
861.9
None of these is correct
210
-97
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: Fede = Frdr. In this problem we're looking for resistance force:
\( F_r = \frac{F_e d_e}{d_r} \)
\( F_r = \frac{210 \times 0.5}{0.5} \)
\( F_r = \frac{105.0}{0.5} \)
\( F_r = 210 \)
4 What is the mechanical advantage of this inclined plane if the length of the ramp is 2 ft. and the height of the green box is 1 ft.?
82% Answer Correctly
2.2
6
1.8
2
Solution

The mechanical advantage (MA) of an inclined plane is the effort distance divided by the resistance distance. In this case, the effort distance is the length of the ramp and the resistance distance is the height of the green box:

MA = \( \frac{d_e}{d_r} \) = \( \frac{2 ft.}{1 ft.} \) = 2

5

Specific gravity is a comparison of the density of an object with the density of:

57% Answer Correctly

water

air

carbon

oil
Solution

Specific gravity is the ratio of the density of equal volumes of a substance and water and is measured by a hyrdometer.