Plus printable tests, Q&A, and an ad-free upgrade. Have a suggestion? Please let us know what you want!
Take an ASVAB Practice Test
Sample Practice Test Questions
The mechanical advantage of a wheel and axle is the input radius divided by the output radius:
MA = \( \frac{r_i}{r_o} \)
In this case, the input radius (where the effort force is being applied) is 5 and the output radius (where the resistance is being applied) is 8 for a mechanical advantage of \( \frac{5}{8} \) = 0.63
For a hydraulic system, pressure applied to the input of the system will increase the pressure in which parts of the system?
all of these are correct
Pascal's law states that a pressure change occurring anywhere in a confined incompressible fluid is transmitted throughout the fluid such that the same change occurs everywhere. For a hydraulic system, this means that a pressure applied to the input of the system will increase the pressure everywhere in the system.
Ignition timing defines the point in time at the end of the compression stroke that which of the following happens?
spark plugs fire
Ignition timing defines the point in time at the end of the compression stroke that the spark plug fires. Measured in number of degrees before top dead center (BTDC), the exact point that the spark plugs initiate combustion varies depending on the speed of the engine. The timing is advanced (the spark plugs fire a few more degrees BTDC) when the engine is running faster and retarded when it's running slower.
Which of the following is not part of the carbon cycle?
precipitation
The carbon cycle represents the ciruit of carbon through Earth's ecosystem. Carbon dioxide (CO_{2}) in the atmosphere is absorbed by plants through photosynthesis. Plants then die and release carbon back into the atmosphere during decomposition or are eaten by animals who breathe (respiration) the carbon into the atmosphere they exhale and produce waste which also releases carbon as it decays.
A block and tackle with four pulleys would have a mechanical advantage of:
4
Two or more pulleys used together constitute a block and tackle which, unlike a fixed pulley, does impart mechanical advantage as a function of the number of pulleys that make up the arrangement. So, for example, a block and tackle with three pulleys would have a mechanical advantage of three.
What is \( \frac{4}{6} \) + \( \frac{4}{14} \)?
To add these fractions, first find the lowest common multiple of their denominators. The first few multiples of 6 are [6, 12, 18, 24, 30, 36, 42, 48, 54, 60] and the first few multiples of 14 are [14, 28, 42, 56, 70, 84, 98]. The first few multiples they share are [42, 84] making 42 the smallest multiple 6 and 14 share.
Next, convert the fractions so each denominator equals the lowest common multiple:
\( \frac{4 x 7}{6 x 7} \) + \( \frac{4 x 3}{14 x 3} \)
\( \frac{28}{42} \) + \( \frac{12}{42} \)
Now, because the fractions share a common denominator, you can add them:
\( \frac{28 + 12}{42} \) = \( \frac{40}{42} \) = \(\frac{20}{21}\)