Simple machines
This is the ratio of the output force to the input force in a machine.
Mechanical advantage
This is the main element added to iron to produce steel and influence its hardness, strength and ductility.
carbon
This type of motion occurs when an object moves in a straight line, such as a lift travelling vertically.
Linear
This microstructure consists of iron with very little carbon dissolved in it and is relatively soft and ductile.
Ferrite
Can Ms McMillan teach you how to Dougie?
Yes
A machine has an input distance of 2 m and an output distance of 0.5 m. Calculate its velocity ratio.
4
Steel containing approximately 0.07–0.30% carbon belongs to this category.
Low carbon steel
This type of motion occurs when an object rotates around a fixed axis, such as a wheel turning on an axle.
Rotary
In the lead–tin alloy system, this microstructure forms when a liquid alloy transforms into two solid phases simultaneously at the eutectic temperature.
Lamellar microstructure
What animal is Ms McMillan scared of because she thinks they might bite and kick her?
Horses
This simple machine consists of a rigid bar that rotates around a fixed point called a fulcrum.
Lever
As carbon content increases in steel, this property generally increases, while ductility generally decreases.
Hardness
This type of motion involves an object moving repeatedly backwards and forwards along the same path, such as a piston in an engine.
Reciprocating
This hard, brittle iron–carbon compound has the chemical formula Fe₃C.
Cementite
What engineering degree does Ms McMillan have?
Mining
A block and tackle pulley system has a velocity ratio of 6. If the input force is 200 N and the machine is 80% efficient, calculate the output force.
960 N
This iron–carbon microstructure consists of alternating layers of ferrite and cementite and is commonly found in slowly cooled eutectoid steel.
Pearlite
A windscreen wiper moves through an arc in one direction and then reverses direction repeatedly around a pivot. Identify this type of motion.
Oscillatory
On the iron–carbon phase diagram, this high-temperature phase of steel has a face-centred cubic crystal structure and can dissolve significantly more carbon than ferrite.
Austenite
What city was Ms McMillan born in?
Auckland
What is Tashrir's favourite simple machine?
Crowbar
On the iron–carbon phase diagram, this approximate carbon content and temperature represent the eutectoid point, where austenite transforms into pearlite during slow cooling.
Approximately 0.76% carbon and 727°C
This mechanism uses a pivoted lever to change the direction of an applied force, often converting a downward input movement into a horizontal output movement.
This microstructure forms when steel is cooled rapidly enough to trap carbon in a distorted structure, producing a very hard and brittle material.
Martensite
What is the date and month of Ms McMillan's birthday?
20th October