Mixed Deck — All OAR Topics Flashcards

A passage describes how the U.S. Navy transitioned from coal-powered ships to oil-powered vessels in the early 20th century, citing logistical advantages and increased speed. What is the main idea of this passage?

Answer: The Navy's shift to oil power was driven by strategic and operational benefits

The passage focuses on the logistical advantages and speed improvements that motivated the Navy's transition to oil power.

A passage recounts how the Doolittle Raid of 1942, though causing minimal physical damage, provided a major psychological boost to American morale during a difficult period of the war. What is the main idea?

Answer: The raid's significance lay in its morale impact rather than its material damage

The passage emphasizes that the raid's true importance was its psychological effect on American morale, not its physical damage.

A storage facility charges $1.25 per square foot per month. If a unit measures 10 feet by 14 feet, what is the total cost for 6 months?

Answer: $1,050

The unit is 140 sq ft (10 × 14), costing $175/month (140 × $1.25), so 6 months costs $175 × 6 = $1,050.

Read the passage: 'Investigators found that the bridge inspection reports from the previous five years had all been signed by the same engineer—who had retired two years ago—and that the signatures did not match his handwriting samples.' What can be inferred?

Answer: Bridge inspections were being falsified or forged.

Signatures attributed to a retired employee that do not match his actual handwriting strongly imply documents were fraudulently signed.

A 5 kg block on a frictionless surface is pushed by two horizontal forces: 20 N east and 10 N west. What is the magnitude of the block's acceleration?

Answer: 2 m/s²

Net force = 20 − 10 = 10 N east; a = F/m = 10/5 = 2 m/s².

Which of the following is a binomial?

Answer: 3x + 5

A binomial has exactly two terms; 3x + 5 has two terms.

If voltage doubles while resistance stays constant, what happens to power?

Answer: Power quadruples

Since P = V²/R, doubling voltage squares the effect, so power quadruples.

A wrench slips off a bolt head because the wrench opening is slightly too large. This is most likely to cause:

Answer: The bolt head to round off (strip)

An oversized wrench rocks on the corners of the bolt head, shearing them off and rounding the head.

Which of the following best describes a force couple?

Answer: Two equal and opposite forces that produce rotation

A couple consists of two equal, opposite, non-collinear forces that produce pure rotation (torque) with no net linear force.

A fixed pulley is attached to the ceiling to lift a load. What is the primary advantage of this single fixed pulley?

Answer: It changes the direction of the applied force

A single fixed pulley provides a mechanical advantage of only 1 but allows the user to pull downward instead of lifting upward.

An electrical device uses 600 watts of power when connected to a 120-volt source. What is the current flowing through the device?

Answer: 5 amperes

The formula for electrical power is Power (P) = Voltage (V) × Current (I). To find the current, rearrange the formula to I = P / V. Therefore, Current = 600 watts / 120 volts = 5 amperes.

What is the degree of the polynomial 5x³ - 2x + 7?

Answer: 3

The degree is determined by the highest exponent, which is 3.

Simplify: (3x²)(4x³)

Answer: 12x⁵

Multiply coefficients (3×4=12) and add exponents (2+3=5) to get 12x⁵.

A researcher writes: 'While Group A received the standard treatment, Group B received the experimental drug. After eight weeks, Group B showed a 60% reduction in symptoms compared to Group A's 15% reduction.' What can you infer?

Answer: The experimental drug appears more effective than the standard treatment

The significantly greater symptom reduction in Group B compared to Group A suggests the experimental drug is more effective.

Which question is MOST useful for identifying the main idea of a passage?

Answer: What is the author primarily trying to communicate to the reader?

The main idea reflects what the author most wants the reader to understand, making that question the best guide.

A convoy of 8 trucks must deliver 3,200 supply boxes. Each truck can carry 48 boxes per trip. How many complete trips will the entire convoy need to make to deliver all boxes?

Answer: 9 trips

Boxes per trip (whole convoy) = 8 x 48 = 384 boxes; trips = 3,200 / 384 = 8.33, so 9 complete trips are needed.

Which expression is equivalent to 4x² - 8x?

Answer: 4x(x - 2)

Factor out 4x: 4x(x - 2) = 4x² - 8x.

A 50-kg object moves at 10 m/s. What is its kinetic energy?

Answer: 2500 J

KE = ½mv² = ½ × 50 × 10² = 2500 J.

A force of 40 N is applied to a 10 kg block on a frictionless surface. After 5 seconds, what is the block's velocity if it starts from rest?

Answer: 20 m/s

Acceleration a = F/m = 40/10 = 4 m/s², so v = at = 4 × 5 = 20 m/s.

A passage states that after the new policy was implemented, employee turnover dropped by 40% and satisfaction surveys showed marked improvement. What can you infer about the new policy?

Answer: It had a positive effect on the workplace environment

A drop in turnover and improved satisfaction surveys both indicate the policy positively affected the workplace.