Free ASVAB Practice Tests | ASVAB Test Bank

Electronics Information

Resistance is opposition to which of the following?

current

Resistance is opposition to the flow of current and is measured in ohms (Ω). One ohm is defined as the amount of resistance that will allow one ampere of current to flow if one volt of voltage is applied. As resistance increases, current decreases as resistance and current are inversely proportional.

General Science

The heart __________ blood.

oxygenates

To provide oxygen to the body, blood flows through the heart in a path formed by the right atrium → right ventricle → lungs → left atrium → left ventricle → body. When blood enters the right side of the heart it is deoxygenated. It enters the left side of the heart oxygenated after traveling to the lungs.

Electronics Information

An amplifier is most similar in function to which of the following:

step-up transformer

An amplifier is a device that takes a small input signal and creates a larger output signal. This makes it most similar to a step-up transformer which takes a smaller input voltage and creates a larger output voltage.

Electronics Information

Silver and gold are among the most highly conductive elements. Why is copper used much more often as a conductor in electrical circuits?

all of these

All conductors have resistance and the amount of resistance varies with the element. But, resistance isn't the only consideration when choosing a conductor as the most highly conductive elements like silver and gold are also more expensive and more brittle than slightly less conductive elements like copper. A balance needs to be struck between the electrical qualities of a material and its cost and durability.

General Science

Which of blood component carries oxygen?

red blood cells

Blood is created in bone marrow and is made up of cells suspended in liquid plasma. Red blood cells carry oxygen, white blood cells fight infection, and platelets are cell fragments that allow blood to clot.

Math Knowledge

The endpoints of this line segment are at (-2, 2) and (2, -6). What is the slope-intercept equation for this line?

y = -2x - 2

The slope-intercept equation for a line is y = mx + b where m is the slope and b is the y-intercept of the line. From the graph, you can see that the y-intercept (the y-value from the point where the line crosses the y-axis) is -2. The slope of this line is the change in y divided by the change in x. The endpoints of this line segment are at (-2, 2) and (2, -6) so the slope becomes:

m = $ \frac{\Delta y}{\Delta x} $ = $ \frac{(-6.0) - (2.0)}{(2) - (-2)} $ = $ \frac{-8}{4} $
m = -2

Plugging these values into the slope-intercept equation:

y = -2x - 2

General Science

Velocity and displacement are fully described by both a magnitude and a direction. Velocity and displacement are which of the following?

vector quantities

Velocity and displacement are vector quantities which means each is fully described by both a magnitude and a direction. In contrast, scalar quantities are quantities that are fully described by a magnitude only. A variable indicating a vector quantity will often be shown with an arrow symbol: $\vec{v}$

Math Knowledge

$\sqrt{80}$

If side a = 8, side b = 4, what is the length of the hypotenuse of this right triangle?

$ \sqrt{80} $

According to the Pythagorean theorem, the hypotenuse squared is equal to the sum of the two perpendicular sides squared:

c² = a² + b²
c² = 8² + 4²
c² = 64 + 16
c² = 80
c = $ \sqrt{80} $

Mechanical Comprehension

If the handles of a wheelbarrow are 1.5 ft. from the wheel axle, how many pounds of force must you exert to lift the handles if it's carrying a 130 lbs. load concentrated at a point 0.5 ft. from the axle?

43.3

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: F_ed_e = F_rd_r. In this problem we're looking for effort force:
$ F_e = \frac{F_r d_r}{d_e} $
$ F_e = \frac{130 \times 0.5}{1.5} $
$ F_e = \frac{65.0}{1.5} $
$ F_e = 43.3 $

Mechanical Comprehension

For any given surface, the coefficient of static friction is ___________ the coefficient of kinetic friction.

higher than

For any given surface, the coefficient of static friction is higher than the coefficient of kinetic friction. More force is required to initally get an object moving than is required to keep it moving. Additionally, static friction only arises in response to an attempt to move an object (overcome the normal force between it and the surface).