ASVAB Mechanical Comprehension Practice Test 957415 Results

Your Results Global Average
Questions 5 5
Correct 0 3.00
Score 0% 60%

Review

1

Drag is a type of:

82% Answer Correctly

kinetic energy

work

friction

potential energy
Solution

Drag is friction that opposes movement through a fluid like liquid or air. The amount of drag depends on the shape and speed of the object with slower objects experiencing less drag than faster objects and more aerodynamic objects experiencing less drag than those with a large leading surface area.

2

According to Boyle's law, for a fixed amount of gas kept at a fixed temperature, which of the following are inversely proportional?

63% Answer Correctly

pressure, density

volume, mass

density, volume

pressure, volume
Solution

Boyle's law states that "for a fixed amount of an ideal gas kept at a fixed temperature, pressure and volume are inversely proportional".

3 A mass of air has a pressure of 6.0 psi and a volume of 30 ft.3. If the air is compressed to a new volume of 25 ft.3, what is the new pressure?
56% Answer Correctly
10.2 psi
9.2 psi
7.2 psi
6.5 psi
Solution

According to Boyle's Law, pressure and volume are inversely proportional:

\( \frac{P_1}{P_2} \) = \( \frac{V_2}{V_1} \)

In this problem, V2 = 25 ft.3, V1 = 30 ft.3 and P1 = 6.0 psi. Solving for P2:

P2 = \( \frac{P_1}{\frac{V_2}{V_1}} \) = \( \frac{6.0 psi}{\frac{25 ft.^3}{30 ft.^3}} \) = 7.2 psi

4

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

57% Answer Correctly

aeronautics

physics

mechanics

engineering
Solution

Mechanics deals with motion and the forces that produce motion.

5 If A = 8 ft., B = 3 ft., C = 4 ft., the green box weighs 40 lbs. and the blue box weighs 45 lbs., what does the orange box have to weigh for this lever to balance?
44% Answer Correctly
0 lbs.
120 lbs.
185 lbs.
46.25 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:

40 lbs. x 8 ft. = 45 lbs. x 3 ft. + fC x 4 ft.

320 ft. lbs. = 135 ft. lbs. + fC x 4 ft.

fC = \( \frac{320 ft. lbs. - 135 ft. lbs.}{4 ft.} \) = \( \frac{185 ft. lbs.}{4 ft.} \) = 46.25 lbs.