ASVAB MECHANICAL COMPREHENSION 1 EXAM

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ASVAB MECHANICAL COMPREHENSION #1 EXAM

QUESTIONS

Actual Qs and Ans - Expert-Verified Explanation -Guaranteed passing score -20 Questions and Answers

-Format: Multiple-choice / Flashcard

Question 1: When the 100-pound weight is being slowly hoisted up by the pulley, as shown in the figure above, the downward pull on the ceiling to which the pulley is attached is...

• 50 pounds.
• 100 pounds.
• 150 pounds.
• 200 pounds.

Answer:

C; The downward pull equals the 100-lb. weight being hoisted plus the 50-lb. effort required with the single movable block in the pulley, which has a mechanical advantage of

• 100 lbs. + 50 lbs. = 150 lbs.

Question 2: Study the gear wheels in the figure above, then determine which of the following statements is true.

• If you turn wheel M clockwise by means of the handle, wheel P will also turn clockwise.
• It will take the same time for a tooth of wheel P to make a full turn as it will for a tooth of

wheel M.

• It will take less time for a tooth of wheel P to make a full turn than it will take a tooth of wheel

M.

• It will take more time for a tooth of wheel P to make a full turn than it will for a tooth of wheel

M.

Answer:

D; Wheel P has 16 teeth; wheel M has 12 teeth. When wheel M makes a full turn, wheel P will still have

• more teeth to turn. So, wheel P is slower and will take more time to turn.

Question 3: Which pulley arrangement shown above requires the LEAST force at F to lift the weight?

• A
• B
• C
• All three require the same force.

Answer:

A; The mechanical advantage is calculated by the number of strands supporting the weight. A has 3 strands, B has 2, and C has only 1.

Question 4: The simple machine pictured above is a form of...

• pulley.
• spur gear.
• inclined plane.
• worm gear.

Answer:

B; An inclined plane is a sloping, triangular shape, used here as a wedge to force open an axe cut made in the log.Question 5: In the diagram above, the axle 8 inches in diameter has attached a handle 28 inches in diameter. If a force of 50 pounds is applied to the handle, the axle will lift a weight of...

• 224 pounds.
• 175 pounds.

• 200 pounds.
• 88 pounds.

Answer:

B; The diameter of the handle is 3 ½ times (28/3) the diameter of the axle. When 50 Ibs. of force is applied to the handle, it is multiplied by 3 ½ times, or, 28/8 x 50= 175 Ibs.Question 6: The figure above shows a brass and an iron strip continuously riveted together.High temperatures would probably...

• have no effect at all.
• bend the strips.
• separate the strips.
• shorten the strips.

Answer:

B; The figure shown is a bimetallic strip that works like the wire in a thermostat. High temperatures will cause the metals to heat unevenly. The rivets will keep the strips together, so the only thing that they can do is bend.

Question 7: The main purpose of expansion joints in steam lines is to...

• provide for changes in the length of the heated pipe.
• allow for the connection of additional radiators.
• provide locations for valves.
• reduce breakage of the pipe due to minor movement of the building frame.

Answer:

D; The water shut-off valve on a flush tank is closed by the force of a lightweight ball rising inside the tank. If this float becomes waterlogged, it will not rise and shut off the water.Question 8: What effort must be exerted to lift a 60-pound weight in the figure of a first-class lever shown above (disregard the weight of the lever in your computation)?

• 30 pounds
• 36 pounds

• 45 pounds
• 60 pounds

Answer:

B; Let x= effort that must be exerted. 60 x 3= x times 5= 5x; x=80/5=36

Question 9: Which of the following statements is true about the figure above?

• If the nut is held stationary and the head is turned clockwise, the bolt will move up.
• If the head of the bolt is held stationary and the nut is turned clockwise, the nut will move

down.

• If the head of the bolt is held stationary and the nut is turned clockwise, the nut will move up.
• If the nut is held stationary and the bolt is turned counterclockwise, the nut will move up.

Answer:

B; Clockwise is right to left, so if the nut moves, it follows the threads of the bolt downward.Question 10: For the turnbuckle shown above, the number of complete turns of Part 1 required to make the ends of the threaded rods meet is...

• 6
• 18
• 12
• 24

Answer:

C; The trick with this question is that both of the rods will be pulled in at the same time when the turnbuckle is turned. If it is turned 12 times (12 threads per inch), both rods will be pulled in 1 inch.Question 11: Eight gallons of water per minute are flowing at a given time from the 1-inch outlet in the tank shown above. What is the amount of water flowing at that time from the 2-inch outlet?

• 64 gallons per minute
• 32 gallons per minute
• 16 gallons per minute