stuff Flashcards
(150 cards)
1
Q
What do gears do?
A
Gears help transfer motion and power from one part of a machine to another.
2
Q
What is a gear ratio?
A
A gear ratio shows how many times one gear turns compared to another.
3
Q
How do you find the gear ratio?
A
Divide the number of teeth on the driven gear by the number of teeth on the drive gear.
GearRatio=TeethonDrivenGear / TeethonDriveGear
4
Q
If Gear A has 12 teeth and Gear B has 36 teeth, what’s the gear ratio?
A
The gear ratio is 36 / 12 = 3. Gear B turns 1 / 3 as fast as Gear A.
5
Q
What happens if you add more teeth to the driven gear?
A
The driven gear will turn slower.
6
Q
How does torque change with gear ratio?
A
More gear ratio means more torque on the driven gear
7
Q
How do you find the torque on the driven gear?
A
Multiply the torque on the drive gear by the gear ratio.
TorqueonDrivenGear=TorqueonDriveGear×GearRatio
8
Q
What is a spur gear?
A
A spur gear has straight teeth and is used for gears on parallel shafts.
9
Q
What is an epicyclic gear train?
A
It’s a system with gears rotating around a central gear.
10
Q
How do you calculate the gear ratio in an epicyclic gear train with a fixed ring gear?
A
GearRatio= TeethonRingGear + TeethonSunGear / TeethonSunGear
11
Q
If the ring gear has 50 teeth and the sun gear has 10 teeth, what’s the gear ratio?
A
The gear ratio is 50+10/10=6
12
Q
What does a gear reducer do?
A
It makes the output turn slower and with more force.
13
Q
How do you find the output speed of a gear train?
A
Multiply the input speed by the gear ratio.
OutputSpeed=InputSpeed×(TeethonInputGear/TeethonOutputGear)
14
Q
How does the driven gear’s rotation compare to the drive gear’s rotation?
A
The driven gear turns in the opposite direction.
15
Q
What is gear mesh?
A
Gear mesh is when two gears fit together and turn each other.
16
Q
What is the purpose of a gear’s teeth?
A
The teeth on a gear grip the teeth of another gear to transfer motion and force.
17
Q
What happens when two gears with different sizes mesh?
A
The smaller gear turns faster than the larger gear.
18
Q
What does a gear train do?
A
A gear train connects multiple gears to change the speed and direction of rotation.
19
Q
What is the pitch of a gear?
A
The pitch is the distance between the teeth on a gear.
20
Q
What is a bevel gear used for?
A
A bevel gear changes the direction of rotation by 90 degrees.
21
Q
What is the name of the gear that rotates around another gear?
A
The planet gear.
22
Q
What is a worm gear used for?
A
A worm gear is used to turn shafts at right angles and provide a large gear reduction.
23
Q
In a gear system, what does “meshing” mean?
A
Meshing means the teeth of two gears are interlocking to transfer motion.
24
Q
What is the “gear ratio” in simple terms?
A
It’s the ratio of the number of teeth on two gears that tells you how their speeds compare.
25
How does increasing the number of teeth on a drive gear affect the driven gear?
It makes the driven gear turn more slowly.
26
What does the term "output gear" refer to?
The output gear is the gear that receives motion from the input gear and transfers it to another part.
27
Why are gears with the same number of teeth called “identical gears”?
Because they rotate at the same speed and have the same gear ratio.
28
What happens if the input gear and output gear have the same number of teeth?
The output gear turns at the same speed as the input gear.
29
What does the term "gear train" refer to?
A series of gears working together to transmit motion and force.
30
What is the term for the gear that drives other gears?
The drive gear.
31
What are pliers used for?
Pliers are used for gripping, twisting, bending, or cutting objects.
32
What is a screwdriver used for?
A screwdriver is used to turn screws to fasten or remove them.
33
What is the purpose of a wrench?
A wrench is used to tighten or loosen bolts and nuts.
34
What does a hammer do?
A hammer is used to drive nails into materials or break objects.
35
What is a tape measure used for?
A tape measure is used to measure length or distance.
36
What is the function of a level?
A level is used to determine if a surface is horizontal or vertical.
36
What is a saw used for?
A saw is used to cut through materials like wood or metal.
37
What is a drill used for?
A drill is used to make holes in materials and can also drive screws.
37
What is a chisel used for?
A chisel is used to carve or cut hard materials like wood or metal.
37
What is a clamp used for?
A clamp is used to hold objects securely in place.
38
What does a socket set include?
A socket set includes various sizes of sockets and a ratchet handle for tightening or loosening bolts.
39
What is a utility knife used for?
A utility knife is used for cutting materials like paper, cardboard, and plastic.
40
What is a combination wrench?
A combination wrench has a box-end and an open-end for different types of fasteners.
40
What is a file used for?
A file is used to smooth or shape materials, usually metal or wood.
40
What is the purpose of an adjustable wrench?
An adjustable wrench can be adjusted to fit different sizes of nuts and bolts.
41
What is a crowbar used for?
A crowbar is used to pry apart objects or lift heavy items.
42
What is a pipe wrench used for?
A pipe wrench is used to grip and turn pipes and other cylindrical objects.
43
What does a ratchet tool do?
A ratchet tool allows you to turn fasteners without removing the tool from the fastener.
44
What is a hex key (Allen wrench) used for?
A hex key is used to drive screws with a hexagonal socket.
45
What is a multimeter used for?
A multimeter measures electrical values like voltage, current, and resistance.
45
What is the purpose of a torque wrench?
A torque wrench is used to apply a specific amount of torque to a fastener.
46
What is a jigsaw used for?
A jigsaw is used for making curved cuts in wood or other materials.
46
What is the function of a pipe cutter?
A pipe cutter is used to cut pipes cleanly and precisely.
46
What is a caliper used for?
A caliper is used to measure the dimensions of an object with high accuracy.
47
What is a bench vice used for?
A bench vice holds objects firmly in place while they are being worked on.
47
What does a heat gun do?
A heat gun provides a stream of hot air to heat or soften materials.
48
What is a drill bit used for?
A drill bit is attached to a drill to make holes in various materials.
48
What is the purpose of a soldering iron?
A soldering iron is used to melt solder for joining electrical components.
48
What is the function of a spanner?
A spanner is used to turn nuts and bolts, similar to a wrench.
49
What is a mitre saw used for?
A mitre saw is used to make precise angled cuts in wood or other materials.
50
What is a spring?
A mechanical component that stores and releases energy by deforming and returning to its original shape.
51
What is a compression spring?
A spring designed to resist compressive forces and return to its original length when the force is removed.
51
What are the main types of springs?
Compression springs, tension springs, and torsion springs.
52
What is a tension spring?
A spring designed to resist stretching forces and return to its original length when the force is removed.
53
What is a torsion spring?
A spring designed to resist twisting forces and return to its original shape when the force is removed.
54
What is Hooke's Law?
The principle that the force exerted by a spring is proportional to its extension or compression from its rest position,
𝐹=𝑘𝑥
55
What does the spring constant (k) represent?
The stiffness of the spring, measured in force per unit length (e.g., N/m).
56
What is the formula for the potential energy stored in a spring?
E= 1/2kx^2 where 𝑘 is the spring constant and 𝑥 is the displacement.
57
What is a leaf spring?
A type of spring made from multiple layers of metal (leaves) that work together to absorb shock and provide support.
57
What is a gas spring?
A type of spring that uses compressed gas to provide resistance and support, often used in applications like lift supports.
57
How is the spring constant (k) calculated for a compression spring?
k= x/F where 𝐹 is the force applied and 𝑥 is the extension.
58
What factors affect the performance of a spring?
Material properties, wire diameter, coil diameter, number of coils, and the length of the spring.
59
What is the difference between a linear and a nonlinear spring?
A linear spring follows Hooke’s Law with a constant spring constant, while a nonlinear spring does not, and its force-displacement relationship varies.
59
What is a coil spring?
A type of compression or tension spring made of a coiled wire that provides resistance to axial forces.
60
What is the difference between a helical spring and a torsion spring?
A helical spring resists compressive or tensile forces along its axis, while a torsion spring resists rotational forces around its axis.
61
What is spring fatigue?
The weakening of a spring over time due to repeated loading and unloading cycles.
61
How does increasing the wire diameter affect the spring constant?
Increasing the wire diameter increases the spring constant, making the spring stiffer.
62
What is the formula for the spring constant of a helical compression spring?
k=Gd^4/8D^3n where 𝐺 is the modulus of rigidity, 𝑑 is the wire diameter, 𝐷is the mean coil diameter, and 𝑛 is the number of active coils.
63
What is the impact of increasing the number of coils in a spring?
Increasing the number of coils decreases the spring constant, making the spring more flexible.
64
What materials are commonly used for springs?
High-carbon steel, stainless steel, and alloy steels.
65
What is a spring’s free length?
The length of a spring when no external force is applied.
65
How does temperature affect spring performance?
Temperature changes can alter the material properties of the spring, affecting its spring constant and overall performance.
66
What is the difference between a constant-rate and a variable-rate spring?
A constant-rate spring has a uniform spring constant, while a variable-rate spring has a changing spring constant.
67
What is a Belleville spring?
A type of spring that uses conical washers stacked together to provide high force in a compact form.
68
What is a torsion spring’s primary application?
Used in applications requiring rotational force, such as garage door mechanisms and clip hinges.
69
What is preload in a spring?
The initial load or force applied to a spring when it is in its uncompressed or unextended state.
70
What is the effect of increasing the coil diameter in a helical spring?
Increasing the coil diameter decreases the spring constant, making the spring more flexible.
71
What is a spring’s maximum working load?
The maximum force that can be applied to a spring without causing permanent deformation.
72
What is the significance of spring rate in a suspension system?
The spring rate determines how much the suspension will compress under load, affecting ride quality and handling.
73
What is a variable pitch spring?
A spring where the spacing between coils varies along its length, providing a changing spring constant.
74
What is an electrical circuit?
A path through which electric current flows, consisting of components such as resistors, capacitors, and power sources.
75
What is a resistor?
A component that opposes the flow of electric current, causing a voltage drop.
76
What is Ohm's Law?
The principle stating that the current through a conductor between two points is directly proportional to the voltage across the two points, V=IR.
77
What does the symbol "R" represent in Ohm's Law?
Resistance, measured in ohms (Ω).
77
What does the symbol "V" represent in Ohm's Law?
Voltage, measured in volts (V).
78
What does the symbol "I" represent in Ohm's Law?
Current, measured in amperes (A).
79
What is a capacitor?
A component that stores electrical energy in an electric field and releases it when needed.
80
What is a series circuit?
A circuit where components are connected end-to-end, so the same current flows through each component.
80
What is the unit of capacitance?
Farad (F).
81
What is a parallel circuit?
A circuit where components are connected across the same voltage source, providing multiple paths for current to flow.
82
What is the formula for total resistance in a series circuit?
Resistance(R) total = R1 + R2 + R3 +...
83
What is the formula for total resistance in a parallel circuit?
1/Resistance(R) total = 1/R1 + 1/R2 + 1/R3 +...
84
What is an inductor?
A component that stores energy in a magnetic field when current flows through it.
84
What is the unit of inductance?
Henry (H).
85
What is a circuit breaker?
A safety device that automatically stops the flow of current in a circuit when it detects an overload or short circuit.
86
What is a pulley?
A simple machine consisting of a wheel with a groove around its edge that holds a rope or belt.
87
What is the main purpose of a pulley?
To change the direction of the force applied or to gain a mechanical advantage.
88
What is a fixed pulley?
A pulley that is attached to a fixed location and changes the direction of the applied force.
89
What is a movable pulley?
A pulley that moves with the load and reduces the amount of force needed to lift the load.
90
What is mechanical advantage in a pulley system?
The factor by which a pulley system multiplies the force applied to it.
90
What is a compound pulley system?
A system that combines fixed and movable pulleys to increase mechanical advantage.
91
How is the mechanical advantage of a pulley system calculated?
By counting the number of rope segments supporting the load.
92
What is the formula for mechanical advantage (MA) in a pulley system?
MA= Load/Effort
93
What is the difference between a block and tackle and a single fixed pulley?
A block and tackle system provides greater mechanical advantage by using multiple pulleys.
94
What is the purpose of a block and tackle system?
To provide a high mechanical advantage for lifting heavy loads.
95
What is a single fixed pulley?
A pulley with a fixed position that changes the direction of the force but does not change the magnitude of the force.
96
What is a single movable pulley?
A pulley that moves with the load and halves the amount of effort required to lift it.
97
What is the effect of adding more pulleys to a system?
More pulleys increase the mechanical advantage but may also increase the length of rope needed.
98
What is the principle of conservation of energy in a pulley system?
The work input equals the work output; more effort is needed to lift a load with greater mechanical advantage, but the effort is reduced.
99
What is a fixed pulley’s impact on the direction of force?
It changes the direction of the force applied but does not affect the amount of force needed.
100
What is a movable pulley’s impact on the force needed?
It reduces the amount of force needed to lift a load by distributing the weight.
101
What is a sheave?
A wheel or disk with a groove for a belt or rope, commonly used in pulley systems.
102
What is the difference between a pulley and a winch?
A winch is a device that uses a crank or motor to wind up a rope or cable, often incorporating pulleys.
103
What is the primary advantage of using pulleys in construction?
They allow for easier lifting and moving of heavy loads with less effort.
104
How does friction affect a pulley system?
Friction can reduce the efficiency of the pulley system, requiring more effort to lift the load.
105
What is a lever?
A simple machine consisting of a rigid bar that pivots around a fixed point, called a fulcrum, to move a load.
106
What is a fulcrum?
The fixed point on which a lever pivots or rotates.
107
What is the formula for mechanical advantage in a lever?
MA= Length effort arm / Length load arm
108
What is a first-class lever?
A lever where the fulcrum is placed between the effort and the load (e.g., seesaw).
108
What is the load in a lever system?
The object or weight that the lever is used to move or lift.
109
What is the effort in a lever system?
The force applied to the lever to move the load.
109
What is mechanical advantage (MA) in a lever?
The ratio of the load force to the effort force, which shows how much the lever amplifies the input force.
110
What is a second-class lever?
A lever where the load is placed between the fulcrum and the effort (e.g., wheelbarrow).
111
What is a third-class lever?
A lever where the effort is applied between the fulcrum and the load (e.g., a fishing rod).
112
How does a first-class lever provide mechanical advantage?
It can increase force or speed, depending on the relative lengths of the effort arm and the load arm.
113
How does a second-class lever provide mechanical advantage?
It always increases force, as the effort arm is longer than the load arm.
114
How does a third-class lever affect force and speed?
It increases speed or range of motion but requires more effort force than the load force.
115
What is the effort arm in a lever?
The distance from the fulcrum to the point where the effort is applied.
116
What is the load arm in a lever?
The distance from the fulcrum to the load being moved.
117
Give an example of a first-class lever.
A seesaw or crowbar.
117
What is the primary function of a lever?
To amplify an input force to lift or move a load more easily.
118
Give an example of a third-class lever.
A fishing rod or a pair of tweezers.
118
How does the length of the effort arm affect the mechanical advantage?
A longer effort arm increases mechanical advantage, reducing the force needed to lift the load.
118
What is the relationship between work input and work output in a lever system?
Work input equals work output, but a lever redistributes the force to make the task easier.
118
Give an example of a second-class lever.
A wheelbarrow or a nutcracker.
119
How does the length of the load arm affect the mechanical advantage?
A shorter load arm increases mechanical advantage, making it easier to lift the load.
119
Why do second-class levers always have a mechanical advantage greater than 1?
Because the effort arm is always longer than the load arm.
120
What is the trade-off when using a lever with high mechanical advantage?
Less force is required, but the effort must be applied over a greater distance.
121
What is the disadvantage of third-class levers?
They require more effort force than the load force but increase speed and range of motion.
122
How can levers be combined with other simple machines?
Levers can be combined with pulleys, wheels, and axles to further reduce effort and increase efficiency.
