ADF ADF Mechanical Reasoning 2 — Questions and Answers
Question 1: A force of 10 N is applied at the rim of a wheel with a radius of 0.5 m. What is the torque produced?
- 0.5 Nm
- 5 Nm (Correct answer)
- 10 Nm
- 20 Nm
Correct answer: 5 Nm
Torque = Force × perpendicular distance from pivot; 10 N × 0.5 m = 5 Nm.
Question 2: Two objects of different mass are dropped simultaneously from the same height in a perfect vacuum. What happens?
- The heavier object hits first
- The lighter object hits first
- Both objects hit the ground at the same time (Correct answer)
- The result depends on the objects' shapes
Correct answer: Both objects hit the ground at the same time
In a vacuum, gravitational acceleration is equal for all objects regardless of mass, so both objects reach the ground simultaneously.
Question 3: According to Pascal's Law, what happens to pressure when force is applied to a confined fluid?
- Pressure increases only at the point of application
- Pressure is transmitted equally throughout the fluid (Correct answer)
- Pressure decreases at the far end of the fluid
- Pressure is absorbed by the container walls
Correct answer: Pressure is transmitted equally throughout the fluid
Pascal's Law states that pressure applied to an enclosed, incompressible fluid is transmitted undiminished in all directions throughout the fluid.
Question 4: A bolt has a thread pitch of 2 mm. How many complete turns are required to advance it 10 mm into a surface?
- 2 turns
- 5 turns (Correct answer)
- 10 turns
- 20 turns
Correct answer: 5 turns
Turns required = distance ÷ pitch; 10 mm ÷ 2 mm per turn = 5 complete turns.
Question 5: In a circuit, if resistance doubles while voltage remains constant, what happens to the current?
- Current doubles
- Current halves (Correct answer)
- Current stays the same
- Current quadruples
Correct answer: Current halves
Ohm's Law states I = V ÷ R; if R doubles and V is constant, current I is halved.
Question 6: What is the primary purpose of ball bearings in a mechanical system?
- To increase friction for better grip
- To reduce friction between rotating and stationary parts (Correct answer)
- To provide structural load-bearing support only
- To add mass for stability
Correct answer: To reduce friction between rotating and stationary parts
Ball bearings replace sliding friction with rolling friction between moving components, dramatically reducing energy loss and wear.
ADF ADF Mechanical Reasoning 2
A force of 10 N is applied at the rim of a wheel with a radius of 0.5 m.
What is the torque produced?