Texas Civil Service Exam Mechanical and Spatial Aptitude 2 — Questions and Answers
Question 1: A lever has a fulcrum placed 2 feet from a 100-pound load and 8 feet from the applied force. How much force is needed to lift the load?
- 25 pounds (Correct answer)
- 50 pounds
- 100 pounds
- 200 pounds
Correct answer: 25 pounds
Using the lever principle: Force × 8 = 100 × 2, so Force = 200/8 = 25 pounds.
Question 2: Which type of gear arrangement reverses the direction of rotation between the input and output shaft?
- Worm gear
- Bevel gear
- Spur gear pair (Correct answer)
- Planetary gear
Correct answer: Spur gear pair
A spur gear pair (two meshing spur gears) causes the output gear to rotate in the opposite direction from the input gear.
Question 3: A cube is painted red on all sides and then cut into 27 equal smaller cubes. How many small cubes have exactly two red faces?
- 8
- 12 (Correct answer)
- 6
- 1
Correct answer: 12
Edge cubes (not corners) have exactly two painted faces; a 3×3×3 cube has 12 edge positions.
Question 4: Water flows through a pipe at 4 gallons per minute. If the pipe narrows so its cross-section is halved, what happens to the flow velocity?
- It halves
- It stays the same
- It doubles (Correct answer)
- It quadruples
Correct answer: It doubles
By the continuity equation, if area is halved and flow rate is constant, velocity must double.
Question 5: A flat piece of metal is bent as shown: top view looks like an 'L'. When viewed from the front, what shape would you see?
- A rectangle (Correct answer)
- An L-shape
- A triangle
- A square
Correct answer: A rectangle
Viewed from the front, the bent L-shape appears as a flat rectangle because the bend goes away from you.
Question 6: A pulley system uses one fixed and one movable pulley. If you pull the rope 4 feet, how far does the load rise?
- 1 foot
- 2 feet (Correct answer)
- 4 feet
- 8 feet
Correct answer: 2 feet
A single movable pulley provides a mechanical advantage of 2, so the load rises half the distance the rope is pulled.
Question 7: Which of the following best describes how a torque wrench works?
- It measures the weight of the bolt
- It applies and measures rotational force (Correct answer)
- It cuts threads into metal
- It removes stripped bolts
Correct answer: It applies and measures rotational force
A torque wrench measures and limits the rotational force (torque) applied to a fastener to prevent over-tightening.
Texas Civil Service Exam Mechanical and Spatial Aptitude 2
A lever has a fulcrum placed 2 feet from a 100-pound load and 8 feet from the applied force.
How much force is needed to lift the load?