Mechanical Comprehension for ASVAB Power Practice Problems

These mechanical comprehension practice questions are based on the actual ASVAB. Take this quiz to see how you would do if you took the exam today and to determine your strengths and weaknesses as you plan your study schedule.

Time: 19 minutes

1. Using the pulley system shown here, how much force is required to lift a 276-pound load?
   1. 49 pounds
   2. 92 pounds
   3. 138 pounds
   4. 276 pounds



2. The water system in tank A has been contaminated. In what order can the valves be opened to empty tank A through the outlet and then refill it from tank C?
   1. open 4, then open 2
   2. open 5 and 4, then open 3
   3. open 5 and 3, then open 2
   4. open 3 and 4, then open 2
3. Ice cubes float on top of water because
   1. ice is a solid.
   2. ice is hollow.
   3. ice is denser than water.
   4. ice is less dense than water.



4. In the diagram shown here, Shannon wants to lift a 100-pound block using a lever. If the block is 9 feet from the pivot point and Shannon is 11 feet beyond that, how much force must she apply to lift the block?
   1. 45 pounds
   2. 99 pounds
   3. 100 pounds
   4. 109 pounds



5. Gear 1 has 12 teeth and gear 2 has 9. If gear 2 turns at 60 rpm, how fast will gear 1 turn?
   1. 15 rpm
   2. 30 rpm
   3. 45 rpm
   4. 60 rpm



6. The arm of a crane is 16 feet long, and the cable used to lift the arm is attached 10 feet from the crane body. For the crane to lift an object weighing 600 pounds, how much force must be applied by the cable?
   1. 160 pounds
   2. 600 pounds
   3. 960 pounds
   4. 1,600 pounds



7. A 500-pound block is being pulled up an incline by a pulley. The incline is 24 feet long and rises 6 feet. Neglecting friction, how much force is necessary to move the block up the incline?
   1. 125 pounds
   2. 500 pounds
   3. 144 pounds
   4. 476 pounds
8. Jill leaves her house in a car and travels north at 40 mph. Alex leaves from the same place one hour later and follows the same route at 60 mph. How long will Alex have to drive before he overtakes Jill?
   1. 40 minutes
   2. 1 hour
   3. 2 hours
   4. 3 hours



9. Pulley B has twice the circumference of pulley A. If pulley A rotates at 20 revolutions per minute (rpm), how fast must pulley B rotate?
   1. 10 rpm
   2. 20 rpm
   3. 40 rpm
   4. 200 rpm



10. A spring has a force constant of 2.5 pounds per inch. How much force is required to move the spring 10 inches?
    1. 4 pounds
    2. 12.5 pounds
    3. 25 pounds
    4. 50 pounds
11. Styrofoam cups do well at keeping coffee warm because they
    1. are good insulators.
    2. are poor insulators.
    3. absorb light and convert it to heat.
    4. transfer heat from your hand to the coffee.
12. A screw has 20 threads per inch. How many full turns of the nut are required for the nut to travel 1.5 inches?
    1. 15 turns
    2. 20 turns
    3. 25 turns
    4. 30 turns
13. When oil and water are mixed together, the oil forms a layer at the top, and the water sinks to the bottom because
    1. oil is less dense than water.
    2. oil is denser than water.
    3. oil is more acidic than water.
    4. oil is less acidic than water.



14. A series of springs with force constants of 2, 3, and 6 pounds per inch support a platform. When a 6-pound block is lowered onto it, how many inches does the platform compress?
    1. 4 inches
    2. 5 inches
    3. 6 inches
    4. 7 inches



15. In the diagram shown here, Dave wants to lift a 180-pound block using a lever. If the block is 4 feet from the pivot point and Dave is 9 feet from the pivot point, how much force must he apply to lift the block?
    1. 36 pounds
    2. 80 pounds
    3. 120 pounds
    4. 180 pounds



16. Using the pulley system shown here, how much force is required to lift a 200-pound weight?
    1. 50 pounds
    2. 100 pounds
    3. 150 pounds
    4. 200 pounds
17. An ax is a form of what simple machine?
    1. a lever
    2. a pulley
    3. an inclined plane
    4. a gear



18. What is the mechanical advantage of the pulley system shown here?
    1. 1
    2. 2
    3. 3
    4. 4



19. If gear 1 turns clockwise, which other gear(s), if any, will also turn clockwise?
    1. 2 only
    2. 3 only
    3. 2 and 3
    4. none



20. A 200-pound block is being pulled up an incline by a pulley. The incline rises 10 feet. Neglecting friction, if 50 pounds of force is necessary to move the block up the incline, how long is the incline?
    1. 30 feet
    2. 20 feet
    3. 40 feet
    4. 100 feet
21. A single-speed bicycle has a front chain ring with 48 teeth. The back gear has 16 teeth. If the bicycle is pedaled for 3 revolutions, how many complete revolutions will the rear wheel make?
    1. 3
    2. 9
    3. 16
    4. 48
22. What causes the pistons in an engine to move when the fuel-air mixture is ignited in the combustion chamber?
    1. The heat from the explosion gives the pistons energy.
    2. The high pressure created from the ignition forces the piston down.
    3. Electrical energy moves the piston.
    4. Momentum from the other pistons.
23. Which material would be optimal for constructing a boat anchor?
    1. wood
    2. metal
    3. glass
    4. plastic



24. In the diagram, Nadine wants to balance two blocks on either side of a lever. One block weighs 85 pounds, and the other weighs 45 pounds. If the 85-pound block is 9 feet to the left of the pivot point, how far to the right of the pivot point should the 45-pound block be placed?
    1. 15 feet
    2. 9 feet
    3. 18 feet
    4. 17 feet
25. A bicycle has one front chain ring with 48 teeth and two possible gears on the back wheel: one with 16 teeth and one with 12 teeth. If the bike with the 16-tooth cog is pedaled at 80 rpm, how fast would the bike with the 12-tooth cog have to be pedaled to go the same speed?
    1. 60 rpm
    2. 80 rpm
    3. 100 rpm
    4. 120 rpm