ASVAB Mechanical Comprehension Practice Test 388786 Results

Your Results Global Average
Questions 5 5
Correct 0 3.13
Score 0% 63%

Review

1

On Earth, acceleration due to gravity (g) is approximately __________. 

81% Answer Correctly

6.67 x 10-11 m/s2

1 m/s

9.8 m/s2

1 m/s2
Solution

Newton's Law of Univeral Gravitation defines the general formula for the attraction of gravity between two objects:  \(\vec{F_{g}} = { Gm_{1}m_{2} \over r^2}\) . In the specific case of an object falling toward Earth, the acceleration due to gravity (g) is approximately 9.8 m/s2. 

2 How much work can a 6 hp engine do in 4 seconds?
52% Answer Correctly
13200 ft⋅lb
1 ft⋅lb
12 ft⋅lb
24 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:
\( W = 6 hp \times 550 \frac{ft⋅lb}{s} \times 4s = 13200 ft⋅lb \)
3 If A = 11 ft., B = 3 ft., C = 10 ft., the green box weighs 50 lbs. and the blue box weighs 65 lbs., what does the orange box have to weigh for this lever to balance?
44% Answer Correctly
142 lbs.
550 lbs.
35.5 lbs.
0 lbs.
Solution
In order for this lever to balance, the torque acting on each side of the fulrum must be equal. So, the torque produced by A must equal the torque produced by B and C. Torque is weight x distance from the fulcrum which means that the following must be true for the lever to balance:

fAdA = fBdB + fCdC

For this problem, this equation becomes:

50 lbs. x 11 ft. = 65 lbs. x 3 ft. + fC x 10 ft.

550 ft. lbs. = 195 ft. lbs. + fC x 10 ft.

fC = \( \frac{550 ft. lbs. - 195 ft. lbs.}{10 ft.} \) = \( \frac{355 ft. lbs.}{10 ft.} \) = 35.5 lbs.

4

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

66% Answer Correctly

dynamic load

impact 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.

5

Normal force is generally equal to the __________ of an object.

61% Answer Correctly

coefficient of friction

density

mass

weight
Solution

Normal force arises on a flat horizontal surface in response to an object's weight pressing it down. Consequently, normal force is generally equal to the object's weight.