Free Mechanical Aptitude Ultimate Question and Answers — Questions and Answers
Question 1: The most powerful force in a cutting process is
- Radial force
- Force along shear plane
- Axial or Longitudinal force
- Tangential force (Correct answer)
Correct answer: Tangential force
In a cutting process, the tangential force, also known as the cutting force, is the most powerful force. It acts in the direction of the cutting velocity and is primarily responsible for overcoming the material's resistance to deformation and separation. This force dictates the power required for the machining operation.
Question 2: In the event that the material is ductile and the cutting speed is high, then
- Discontinues chips are formed
- Continuous chips with built up edges are formed
- Continuous chips are formed (Correct answer)
- None of the above
Correct answer: Continuous chips are formed
When machining ductile materials at high cutting speeds, the material undergoes continuous plastic deformation ahead of the cutting tool. This leads to the formation of long, unbroken chips that flow smoothly over the tool's rake face. These are known as continuous chips, indicating stable and efficient cutting conditions.
Question 3: 250 gallons of product are being transferred from Tank A to Tank B at a rate of 10 gallons per hour. Already, 30 gallons have been moved to Tank B. How much time is left until the transfer is finished?
- 24 hours
- 20 hours
- 25 hours
- 22 hours (Correct answer)
Correct answer: 22 hours
To find the remaining time, first calculate the amount of product still to be transferred. With 30 gallons already moved from a total of 250 gallons, 250 - 30 = 220 gallons remain. Since the transfer rate is 10 gallons per hour, divide the remaining amount by the rate: 220 gallons / 10 gallons/hour = 22 hours. Therefore, 22 hours are left until the transfer is finished.
Question 4: Cut depth is determined by
- Rigidity of machine tool
- Tool material
- Cutting speed
- All of the above (Correct answer)
Correct answer: All of the above
The depth of cut in a machining operation is determined by several factors working in conjunction. The rigidity of the machine tool ensures stability under cutting forces, allowing for deeper cuts without excessive deflection. The tool material's strength and wear resistance dictate its ability to withstand the stresses of removing material, and cutting speed influences the overall cutting dynamics and tool life, all contributing to the feasible depth of cut.
Question 5: What among the following won't float on water?
- scissors (Correct answer)
- plastic water bottle
- wooden pencil
- apple
Correct answer: scissors
An object floats on water if its density is less than the density of water. Scissors are typically made of metal, which has a density significantly greater than water. Therefore, scissors will sink when placed in water, unlike items such as plastic bottles (especially if they contain air), wooden pencils, or apples, which have an overall density less than water.
Question 6: What does an orifice plate serve?
- Stop flow
- Increase flow
- Restrict flow (Correct answer)
- None of the above
Correct answer: Restrict flow
An orifice plate is a device commonly inserted into a pipeline to create a deliberate restriction in the flow path. This restriction causes a pressure drop across the plate, which can be utilized for measuring flow rate or simply to reduce and control the flow of a fluid within the system.
Question 7: Liquid capillary motion is caused by the
- Surface tension
- Adhesion of liquid particles on the surface
- Viscosity of liquid
- Cohesion of liquid particles (Correct answer)
Correct answer: Cohesion of liquid particles
Liquid capillary motion, or capillary action, is the ability of a liquid to flow in narrow spaces against gravity. While adhesion (attraction between liquid and surface) causes the liquid to wet and climb the tube walls, the cohesion of liquid particles (attraction between liquid molecules) is crucial for pulling the entire column of liquid upwards as a continuous body. It's the cohesive forces that hold the liquid column together as it rises due to adhesion.
Question 8: Used to cut curves into plastic or wood. (Its flimsiness makes it easier to curve.)
- Coping Saw (Correct answer)
- Brace
- Masonry Drill Bit
- Back Saw (tenon Saw)
Correct answer: Coping Saw
A coping saw is a specialized hand tool designed for cutting intricate curves, shapes, and internal cutouts in wood, plastic, and other soft materials. Its thin, narrow blade can be rotated to navigate tight radii, making it ideal for detailed scrollwork and precise curved cuts that are difficult to achieve with other types of saws.
Question 9: When ordinary screwdrivers won't fit, use this. These screwdrivers also give the operator the option to apply a decent amount of torque to the screw being driven.
- Stubby Screwdriver (close-quarter Screwdriver)
- Torque wrench
- Jewelers screwdriver
- Offset Screwdriver (Cranked Screwdriver) (Correct answer)
Correct answer: Offset Screwdriver (Cranked Screwdriver)
An offset screwdriver, also known as a cranked screwdriver, features a shaft bent at an angle, typically 90 degrees, with screwdriver tips at both ends. This unique design allows it to access and turn screws located in extremely confined or awkward spaces where a straight screwdriver cannot fit, while still providing leverage for applying torque.
Question 10: Used to check whether a piece of work is square.
- Inside Calipers
- Back Saw (tenon Saw)
- Combination Square
- Try Square (Correct answer)
Correct answer: Try Square
A try square is a fundamental measuring and marking tool used in woodworking and metalworking to check and mark right angles (90 degrees). It consists of a metal blade rigidly fixed at a precise right angle to a thicker stock, allowing for accurate verification of squareness on corners, edges, and joints of a workpiece.
Question 11: Used to easily and firmly grasp sheet metal or round metal stock.
- Vise Grips (Plier Wrench) (Correct answer)
- Socket wrench
- Torx screwdriver
- Spark plug wrench
Correct answer: Vise Grips (Plier Wrench)
Vise-Grips, also known as locking pliers or plier wrenches, are versatile hand tools designed to clamp onto objects with adjustable and powerful gripping force. Their locking mechanism allows them to hold sheet metal, round stock, pipes, or other irregularly shaped items firmly in place, freeing the user's hands or providing extra leverage for turning.
Question 12: Used to calculate the ideal tire inflation pressure.
- Socket Wrench
- Ammeter
- Countersink Bit
- Tire Gauge (Correct answer)
Correct answer: Tire Gauge
A tire gauge is a specialized measuring instrument used to determine the air pressure inside vehicle tires. Maintaining the correct tire inflation pressure, as recommended by the vehicle manufacturer, is essential for ensuring vehicle safety, optimizing fuel efficiency, and extending the lifespan of the tires.
Question 13: A hexagonal key with a L shape that is used to tighten and loosen machined setscrews.
- Allen Wrench (Setscrew Wrench) (Correct answer)
- Wrecking bar (crowbar)
- Torque wrench
- Stilson Wrench (pipe Wrench)
Correct answer: Allen Wrench (Setscrew Wrench)
An Allen wrench, also known as a hex key or setscrew wrench, is an L-shaped tool with a hexagonal cross-section. It is specifically designed to fit into and turn screws or bolts that have a hexagonal socket in their head, commonly referred to as setscrews or hex-head screws, found in various machinery and furniture assemblies.
Question 14: Used for swiftly sanding plastic, metals, or wood. On this machine, various abrasives that are embedded in the belts are used in a back and forth motion.
- Belt Sander (Correct answer)
- Reciprocating Saw
- Disk Sander
- Voltmeter
Correct answer: Belt Sander
A belt sander is a powerful electric tool that uses a continuous loop of abrasive material (a sanding belt) to rapidly remove material and smooth surfaces. The belt moves in a linear, back-and-forth motion, making it highly efficient for quickly sanding large flat areas on wood, plastic, or metal, and for shaping or dimensioning workpieces.
Question 15: Used to cut panels' holes. Due to the absence of a frame, unlike the coping saw, this saw is not constrained to a work piece's edge.
- Back Saw (tenon Saw)
- Box wrench
- Compass Saw (Keyhole Saw) (Correct answer)
- Offset wrench
Correct answer: Compass Saw (Keyhole Saw)
A Compass Saw, also known as a Keyhole Saw, is designed with a narrow, tapered blade that allows it to start cuts in the middle of a panel by drilling a pilot hole. Its lack of a frame or bow, unlike a coping saw, provides the flexibility to cut intricate curves and holes without being restricted by the workpiece's edge. This makes it ideal for cutting openings in panels or drywall where access from the edge is not possible.
Question 16: A bit used by a brace with lead screws that are noticeable and helical twists of varied diameters. This describe this kind of wood drilling bit's properties.
- Auger Bit (Twist Bit) (Correct answer)
- Try square
- Compass Saw (keyhole Saw)
- Spade Bit (flat Bit)
Correct answer: Auger Bit (Twist Bit)
An auger bit is specifically designed for drilling deep, clean holes in wood, often used with a brace for manual operation. Its defining features include a prominent lead screw at the tip, which pulls the bit into the wood, and helical flutes (twists) that efficiently clear wood chips from the hole. These characteristics allow for smooth and effective drilling, especially in thicker timber.
The most powerful force in a cutting process is