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Question 1

Wedge

Answer 1

Wedges are very basic simple machines that are made up of two inclined planes placed back to back. Wedges can be used to cut, split, tighten, hold things together, and scrape things.

Question 2

Wheel and Axle

Answer 2

A wheel and axle is made up of a larger disc attached in the centre to a smaller cylinder. Axles and wheels by themselves are not simple machines—only the combination of the two make a simple machine. The circular disc of the wheel acts as a class 1 lever with the axle as the fulcrum. Turning the wheel (the input force) causes that axle to turn (the output force).

Question 3

Lever

Answer 3

A lever is a simple machine consisting of a beam or rigid rod pivoted at a fixed hinge, or fulcrum.

Question 4

Inclined Plane

Answer 4

An inclined plane is a sloped surface that reduces the effort needed to move an object by spreading the required force over a longer distance. While the object is moved a greater distance compared to lifting it directly, the force required is less. This helps make the task of moving objects easier, but the total amount of work remains the same.

Question 5

Screw

Answer 5

A screw is an inclined plane that is wrapped around a cylinder that converts a rotational force to a linear force.

Question 6

Pulley

Answer 6

A pulley is a wheel used in a different way. A pulley consists of a rope and hub or ‘drum’ in which there is a grooved wheel mounted with an axle.

Question 7

Examples of Wedge

Answer 7

Axes
Knives
Screwdrivers

Question 8

Examples of Wheel and Axle

Answer 8

Bicycle
Car
Hand Truck
Wagon

Question 9

Examples of Inclined Plane

Answer 9

Ramp, hill

Question 10

Examples of Screw

Answer 10

Wood Screws
Machine Screws
Sheet Metal Screws

Question 11

Examples of Pulley

Answer 11

Fixed, moveable, compound, and complex

Question 12

Explain the concept of work in relation to simple machines

Answer 12

When a force acts upon an object to cause a displacement of the object, it is said that work was done upon the object.

Question 13

Define Mechanical advantage

Answer 13

Mechanical advantage (MA) is a measure of how much a machine amplifies the input force to perform a task. It is defined as the ratio of the output force exerted by the machine to the input force applied to it. In other words, it tells you how much easier a machine makes it to move a load or perform work.

Question 14

Define power

Answer 14

Power (P) is the rate at which work is done per unit time

Question 15

Explain the relationship between work done, mechanical energy, and power.

Answer 15

Work and Mechanical Energy: Work done alters mechanical energy.
Work and Power: Power is the rate of doing work.
Mechanical Energy and Power: Power measures how quickly mechanical energy changes.

Question 16

Explain the relationship between mechanical advantage and effort required

Answer 16

The mechanical advantage of a machine indicates how effectively it amplifies the applied force. A higher mechanical advantage means less effort is needed to perform a task, though it may require moving the load over a greater distance.

Question 17

Define velocity ratio.

Answer 17

the ratio of a distance through which any part of a machine moves to that which the driving part moves during the same time (VR = DE / DL)

Question 18

Compare and contrast velocity ratio and mechanical advantage

Answer 18

VR relates to speed, while MA relates to force.
Both are ratios, but VR deals with motion and MA with power output.
VR is theoretical, while MA reflects actual performance, influenced by friction and efficiency.

Question 19

Define efficiency and its significance in mechanical systems

Answer 19

Efficiency in mechanical systems is the measure of how effectively a machine converts input energy into useful output energy.

Question 20

Discuss factors affecting efficiency

Answer 20

Friction, materials quality, design of equipment, maintenance

Question 21

Define gear ratio and its relevance in gear systems

Answer 21

Gear Ratio is the ratio of the number of teeth on two interlocking gears or the ratio of their rotational speeds. It determines how torque and speed are transferred between gears in a gear system.

Question 22

If the driver gear is larger than the driven gear, is it a speed multiplier or force multiplier

Answer 22

Increase speed decrease torque

Question 23

If the driven gear is larger than the driver gear, is it a speed multiplier or force multiplier

Answer 23

Increase torque decrease speed

Question 24

VR formula for worm gear

Answer 24

teeth on worm gear / threading of worm wheel

Question 25

Provide examples and practical applications of spur gears

Answer 25

Gearbox in Vehicles: Transfers power between shafts to control speed and torque. Clock Mechanisms: Drives the movement of clock hands with precise timekeeping. Industrial Conveyors: Moves conveyor belts and machinery components. Washing Machines: Powers the drum and agitator for washing clothes. 3D Printers: Controls the movement of the print head and build platform. Toy Cars: Transfers rotational motion from the motor to the wheels for movement.

Question 26

Explain the principle of operation of worm gears

Answer 26

A gear consisting of a shaft with a spiral thread that engages with and drives a toothed wheel. Worm gears are used to transmit power between two shafts that are at right angles to each other and are non-intersecting. This results in significant speed reduction and increased torque. Their self-locking design prevents the worm wheel from driving the worm, making them ideal for applications requiring a secure, non-reversible mechanism.

Question 27

Advantages of worm gear

Answer 27

High speed reduction Compact design Transmit power between non-intersecting shafts Self-locking (no back-driving)

Question 28

Identify practical applications of worm gears

Answer 28

Automotive Steering: Provides precise steering control. Winches: Converts high-speed input to high-torque output. Fishing Reel: Provides smooth line retrieval and precise drag control. Guitar Tuning: Allows fine adjustments to string tension for precise pitch control.

Question 29

Explain the conversion of rotational motion to linear motion in rack and pinion systems

Answer 29

The pinion gear rotates and meshes with the rack, causing the rack to be driven in a straight line.

Question 30

Identify common uses of rack and pinion systems

Answer 30

Steering Systems in Vehicles, Printers, CNC machines

Question 31

What is a bevel gear

Answer 31

A bevel gear is a type of gear designed to transmit motion and torque between shafts that are at an angle to each other, typically at a 90-degree angle. Bevel gears have conical-shaped teeth that mesh with each other, allowing for the transfer of rotational motion and force between intersecting shafts.

Question 32

Provide examples and practical applications of bevel gears

Answer 32

Automobile Differentials: Allow wheels to rotate at different speeds. Hand Drill

Question 33

VR in wheel and axle

Answer 33

2πR (wheel) / 2πr (axle)

Question 34

VR in inclined planes

Answer 34

1 / sin(θ)

Question 35

What is the distance the load moves in inclined planes

Answer 35

the height of the inclined plane

Question 36

VR in screws

Answer 36

Circumference (2πr or πd) / pitch

Question 37

VR in pulleys

Answer 37

Number of rope sections supporting the load

Question 38

How to calculate output speed

Answer 38

output = input / VR

Question 39

VR / gear ratio in gears

Answer 39

(Radius, Diameter, Circumference, #teeth) of driven / (Radius, Diameter, Circumference, #teeth) of driver

Question 40

Types of motion

Answer 40

Rotary, Linear, Reciprocating, Oscillating

Question 41

What is the advantage of a simple machine

Answer 41

It makes work easier by either changing direction, increasing magnitude, increasing the distance or speed of a force or transferring the force from one place to another

Question 42

What is purpose of first class lever

Answer 42

The purpose of a first-class lever is to amplify force and change the direction of applied force. In a first-class lever, the fulcrum (pivot point) is positioned between the input force and the load.

Question 43

What is purpose of second class lever

Answer 43

The purpose of a second-class lever is to increase the mechanical advantage, allowing a smaller effort to lift or move a larger load. In a second-class lever, the load is positioned between the fulcrum and the effort.

Question 44

What is purpose of third class lever

Answer 44

The purpose of a third-class lever is to increase the speed and range of motion of a load rather than to amplify force. In a third-class lever, the effort is applied between the fulcrum and the load.

Question 45

What is a gear

Answer 45

A gear is a rotating machine part used to transmit rotational motion and/or torque by means of a series of teeth that engage with compatible teeth of another gear or other part. Prevents slippage and the change of speed, torque and rotational direction

Question 46

Importance of efficiency,

Answer 46

Cost Savings, performance enhancement, extend equipment life

Question 47

Examples of first class lever

Answer 47

Seesaw Crowbar Pry Bar

Question 48

Examples of second class lever

Answer 48

Wheelbarrow Nutcracker Bottle Opener

Question 49

Examples of third class lever

Answer 49

Tweezers Fishing Rod Broom

Question 50

Ideal MA of First class lever

Answer 50

If the fulcrum is closer to the load, the lever has a mechanical advantage (MA) greater than 1. If the fulcrum is in the middle, MA equals 1.

Question 51

Ideal MA of Second class lever

Answer 51

Greater than 1

Question 52

Ideal MA of Third class lever

Answer 52

Less than 1

Question 53

Are First class levers force multipliers or speed multipliers

Answer 53

Force Multiplier

Question 54

Are Second class levers force multipliers or speed multipliers

Answer 54

Force Multiplier

Question 55

Are Third class levers force multipliers or speed multipliers

Answer 55

Speed Multiplier

Question 56

A wheel and axle belongs to what type of fundamental simple machine?

Answer 56

Lever

Question 57

A screw belongs to what type of fundamental simple machine?

Answer 57

inclined plane

Question 58

What is mechanical energy

Answer 58

Mechanical energy is the sum of kinetic and potential energy within a physical system.