All machines are complex. True or false?
False. Some machines are very simple.
This is a rigid bar that turns around a point
lever
What does a rotary transmission mechanism do?
it connects two rotating elements
A knife, a chisel, the front of a boat are all examples of...
wedges
This word describes a set of elements or parts that work together and use energy to perform a task
machine
What are the three components of a machine?
driver element, driven element, and the converting or transmitting element
What is a third class lever?
A lever where the effort is in between the fulcrum and the resistance
A wheel that has a groove on the outside and roatates around an axis; if we attach a rope, we can use it to lift objects
pulley
screw
Devices that transmit and/or convert motion
mechanisms
In terms of motion, what type of mechanism is a lever?
linear transmission
The fulcrum is always a point that is between the force and the resistance. True or false?
False; this is only true for first class levers.
When using friction wheels, the two wheels rotate in the same direction/different directions. How can we change this?
They rotate in different directions. To change this we can add a third wheel called an idler.
Door knobs, wind turbines, and steering wheels are all examples of...
wheel and axles
The element which feeds energy into a machine
Driver element
What are the types of motion that a mechanism can convert?
linear, rotary, reciprocating, and oscillating
DOUBLE JEOPARDY
What type of lever is a wheelbarrow?
second class lever; the wheel acts as a fulcrum, whatever is inside is the resistance, and the handles are the effort arm
The relationship between the speeds of two wheels is inversely proportional to their sizes. This is called ...
the ration of transmission
Ramp, ladder, and stairs are all examples of...
inclined planes
DOUBLE JEOPARDY
The type of motion in which the object moves forwards and backwards in a straight line
Reciprocating motion
What is the difference between transmission and conversion?
Transmission feeds energy from the driver element to the driven element. Conversion changes the energy somehow.
What class of lever is your arm? Explain your answer.
The arm is a third class lever. The fulcrum is the elbow, the effort is the muscle pulling on the forearm, and the resistance is whatever you are lifting.
Compare and contrast gears and friction wheels. What advantages do gears have?
Gears and friction wheels are both rotary transmission mechanisms but gears have teeth. These teeth prevent gears from slipping like friction wheels.
A stapler is an example of a...
lever
This type of mechanism includes friction wheels, belt and pulley systems, gears, chain and sprockets, and worm gears
Rotary transmission mechanisms