ASVAB ASVAB Certifications ASVAB-SECTION-3 Questions & Answers

• Question 11:

  

  What is the mechanical advantage of this pulley system?

  A. 6

  B. 4

  C. 3

  D. 2

  Correct Answer: C

  In a pulley system, you calculate the mechanical advantage by counting up the number of supporting

  ropes/strands that support the weight.

  In this case, there are 3 supporting strands that support the load, so the mechanical advantage is 3.

• Question 12:

  In the figure below, what is true about supports A and B?

  

  A. The load is equal for both supports

  B. Support A carries more weight

  C. Support B carries more weight

  D. Not enough information

  Correct Answer: C

  Since the load is closer to support B, support B carries more weight.

• Question 13:

  

  Pulling on the rope at point A will lift the load.

  How far will you have to pull the rope at point A to lift the load 15 feet?

  A. 15 feet

  B. 45 feet

  C. 30 feet

  D. 60 feet

  Correct Answer: B

  The mechanical advantage of the pulley is 3 since there are three ropes supporting the load. Therefore, the distance at point A needs to 3x or 3 × 15 = 45 ft.

• Question 14:

  In the figure below, if gear 1 turns counterclockwise (as shown by the arrow), which of the gears will also turn in the same direction?

  

  A. 2 and 4

  B. 2 and 3

  C. 3 and 4

  D. 4

  Correct Answer: C

  Gear 1 turns counterclockwise causing gear 2 to turn clockwise which results in gear 3 and 4 to turn counterclockwise.

• Question 15:

  Which of the following statements is true for water flowing from a 4-inch pipe to a smaller 2-inch pipe?

  A. The same amount of water passes through both the 4-inch pipe and the 2-inch pipe.

  B. The pressure is greater in the 2-inch pipe.

  C. More water passes through the 4-inch pipe than through the 2-inch pipe.

  D. The pressure is lower in the 4-inch pipe.

  Correct Answer: A

  Water cannot be compressed. Therefore, the same amount of water must be flowing through both the 4inch pipe and the 2-inch pipe.

• Question 16:

  Water flows into a container at a rate of 140 gallons per minute. The container has a small opening at the bottom that drains water at a rate of 1 gallon per second.

  How long will it take to fill the container to 240 gallons?

  A. 2 min

  B. 3 min

  C. 4 min D. Not enough information

  Correct Answer: B

  The opening drains water at 1 gallon/second which is equivalent to 60 gallons/min. Therefore, the net gain

  of water is 140 gallons/min - 60/gallons/min = 80 gallons/min.

  To fill 240 gallons at a rate of 80 gallons/min will take 3 minutes.

• Question 17:

  If you use a lever to lift a 200-pound weight with an effort of 40 pounds, with is the mechanical advantage?

  A. 4

  B. 0.2

  C. 8,000

  D. 5

  Correct Answer: D

  Mechanical advantage = load/effort = 200/40 = 5

• Question 18:

  Which of the following would feel hottest at one end if the other end were placed over a fire?

  A. A metal skewer

  B. A wooden stick

  C. A plastic rod

  D. A rubber stick

  Correct Answer: A

  Of the four materials, metal is the best conductor of heat, so a metal skewer would feel the hottest.

• Question 19:

  Which of the following will happen when a mass of air contracts?

  A. The air remains at the same temperature

  B. The air gets colder

  C. The air gets warmer

  D. The air moves faster

  Correct Answer: B

  Air is a gas. According to the gas laws, gasses will get colder when they contract.

• Question 20:

  

  Which of the following is an example of a Class 1 Lever?

  A. Pliers

  B. Wheelbarrow

  C. Tongs

  D. Stapler

  Correct Answer: A

  Pliers are an example of a Class 1 lever (actually 2 class 1 levers).

  Wheelbarrow and stapler are class 2.

  Tongs are class 3.