Mixed Deck — All NSAA Topics Flashcards

A scatter plot shows a correlation coefficient of r = -0.9. This indicates:

Answer: Strong negative correlation

r = -0.9 indicates a strong negative linear correlation between the two variables.

What is the sum of the roots of 3x² - 6x + 2 = 0?

Answer: 2

Sum of roots = -b/a = -(-6)/3 = 2.

Which of the following is the correct definition of standard deviation?

Answer: The square root of the variance

Standard deviation is the square root of the variance, measuring spread around the mean.

A machine does 600 J of work in 30 seconds. What is its power output?

Answer: 20 W

Power = Work/Time = 600/30 = 20 W.

Which of the following is the primary structure of a protein?

Answer: The sequence of amino acids

The primary structure of a protein is the linear sequence of amino acids in its polypeptide chain.

If f(x) = 2x² - 3, what is f(4)?

Answer: 29

f(4) = 2(16) - 3 = 32 - 3 = 29.

During an isothermal process involving an ideal gas, which quantity remains constant?

Answer: Temperature

An isothermal process occurs at constant temperature; for an ideal gas this also means constant internal energy.

The critical angle for a glass-air interface is 42°. What is the refractive index of the glass?

Answer: 1.49

n = 1/sin(θc) = 1/sin(42°) ≈ 1/0.669 ≈ 1.49.

What is the molecular geometry of methane (CH₄)?

Answer: Tetrahedral

Methane (CH₄) has a tetrahedral molecular geometry, with four hydrogen atoms symmetrically distributed around the central carbon atom.

What is the momentum of a 0.5 kg ball moving at 12 m/s?

Answer: 6 kg·m/s

Momentum p = mv = 0.5 × 12 = 6 kg·m/s.

What is the function of ribosomes in the cell?

Answer: Protein synthesis

Ribosomes are responsible for synthesizing proteins by translating messenger RNA.

Which law of thermodynamics is the law of conservation of energy?

Answer: First Law

The first law states that the change in internal energy equals heat added to the system minus work done by the system (ΔU = Q − W), embodying energy conservation.

Which of the following best describes the direction of conventional current in a circuit?

Answer: From positive to negative terminal

By convention, current flows from the positive terminal of the source, through the circuit, to the negative terminal.

In a step-up transformer, the primary coil has 100 turns and the secondary has 500 turns. If the primary voltage is 20 V, what is the secondary voltage?

Answer: 100 V

Vs/Vp = Ns/Np → Vs = 20 × (500/100) = 100 V.

A wire of length 0.5 m carrying 4 A is placed perpendicular to a magnetic field of 0.3 T. What force acts on it?

Answer: 0.6 N

F = BIL = 0.3 × 4 × 0.5 = 0.6 N.

The graph of y = (x-2)² + 3 has its vertex at:

Answer: (2, 3)

In the form y = (x-h)² + k, the vertex is at (h, k) = (2, 3).

If g(x) = 3x + 1, what is g⁻¹(x)?

Answer: (x-1)/3

Set y = 3x+1, swap x and y: x = 3y+1, so y = (x-1)/3.

The integral ∫ 1/x dx equals:

Answer: ln|x| + C

∫ 1/x dx = ln|x| + C.

Solve the inequality: 3x - 4 > 11

Answer: x > 5

3x > 15, so x > 5.

Electromagnetic waves are arranged in the electromagnetic spectrum in order of increasing frequency. Which of the following is the correct order?

Answer: Radio → Visible → X-ray → Gamma

The EM spectrum from lowest to highest frequency: Radio, Microwave, Infrared, Visible, UV, X-ray, Gamma.