ASVAB Mechanical Comprehension Practice Test 765352 Results

Your Results Global Average
Questions 5 5
Correct 0 3.71
Score 0% 74%

Review

1 What is the power output of a 5 hp engine that's 55% efficient?
40% Answer Correctly
1512.5 \( \frac{ft⋅lb}{s} \)
756.3 \( \frac{ft⋅lb}{s} \)
11 \( \frac{ft⋅lb}{s} \)
3025 \( \frac{ft⋅lb}{s} \)
Solution
\( Efficiency = \frac{Power_{out}}{Power_{in}} \times 100 \)
Solving for power out: \( P_{o} = \frac{E \times P_{i}}{100} \)
Knowing that 1 hp = 550 \( \frac{ft⋅lb}{s} \), Pi becomes 5 hp x 550 \( \frac{ft⋅lb}{s} \) = 2750 \( \frac{ft⋅lb}{s} \)
\( P_{o} = \frac{E \times P_{i}}{100} = \frac{55 \times 2750 \frac{ft⋅lb}{s}}{100} \) \( = \frac{151250 \frac{ft⋅lb}{s}}{100} \) = 1512.5 \( \frac{ft⋅lb}{s} \)
2

Which of the following surfaces would have the lowest coefficient of friction?

85% Answer Correctly

tile

ice

leather

concrete
Solution

Coefficient of friction (μ) represents how much two materials resist sliding across each other.  Smooth surfaces like ice have low coefficients of friction while rough surfaces like concrete have high μ.

3

Potential energy is energy that has the potential to be converted into what?

80% Answer Correctly

 kinetic energy

work

power

heat
Solution

Potential energy is the energy of an object by virtue of its position relative to other objects. It is energy that has the potential to be converted into kinetic energy.

4

Collinear forces:

72% Answer Correctly

act along the same line of action

are unrelated to each other

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.

5

The steering wheel of a car is an example of which type of simple machine?

89% Answer Correctly

wheel and axle

block and tackle

fixed pulley

first-class lever
Solution

A wheel and axle uses two different diameter wheels mounted to a connecting axle. Force is applied to the larger wheel and large movements of this wheel result in small movements in the smaller wheel. Because a larger movement distance is being translated to a smaller distance, force is increased with a mechanical advantage equal to the ratio of the diameters of the wheels. An example of a wheel and axle is the steering wheel of a car.