Machines Flashcards
What are simple machines?
device that makes work easier by changing the direction or magnitude of a force
What do simple machines do
They reduce the effort to perform a task
What are inclined planes
its a machine that makes it easier for us to move objects to a higher or lower surface
What is the trade-off (mechanical advantage) of incline planes
If the slope is gentle, a person has to push or pull the object over a longer distance, but with little effort. If the slope is steep, a person has to push or pull the object over a very short distance, but with more effort.
how can a wedge be used
To cut (knife)
To split (axe)
To tighten and to hold back (doorstopper)
To hold together (nail)
To scrape (blades on the snowplow or farm grader)
how does wedges work
it works by changing direction and force applied to it.
The trade-off for wedges
The longer and thinner a wedge is (sharper), the more work it does with little effort. If the wedge is shorter and has a wider angle at the tip, one needs more force to do the work.gh
What is a screw?
A screw is an inclined plane around a cylinder, with a head at one end, a pointed tip at the other, and threads winding around it.
What is the purpose of the thread on a screw?
The thread provides grip and resistance, allowing the screw to hold things together, lift items, and tighten objects.
What is the distance between threads on a screw called?
Pitch
How does a screw differ from a nail in terms of insertion into wood?
A screw requires turning with a screwdriver due to its threads, which create more friction and resistance, unlike a nail which is hammered in directly.
What is a bolt and how is it used differently from a regular screw?
A bolt is a type of screw without a pointed tip, inserted through a pre-made hole and secured with a nut.
What is a drill bit and what is its function?
A drill bit is a type of screw used to create holes in various materials when attached to an electric drill
Mechanical advantage of a screw
Wider thread spacing requires more effort but fewer turns to drive the screw into an object.
What is a lever?
A lever is a plank or rigid beam that is free to rotate on a pivot, used to lift or move heavy objects.
What are the four important parts of a lever?
The four parts are the bar or beam, the fulcrum (pivot), the effort (force), and the load.
What is the role of the beam in a lever?
The beam is a long plank that rests on the fulcrum and is used to apply force and move the load.
What is the fulcrum in a lever?
The fulcrum is the pivot or turning point on which the beam rests and rotates.
How does a lever make work easier?
A lever increases the input force and changes the direction of the input force to lift the load.
What is the arrangement of parts in a Class One Lever?
In a Class One Lever, the fulcrum is between the effort and the load. Examples: seesaws, boat oars, and crowbars.
Where is the load positioned in a Class Two Lever?
In a Class Two Lever, the load is between the effort and the fulcrum. Examples: wheelbarrows.
How is the effort positioned in a Class Three Lever?
In a Class Three Lever, the effort is between the load and the fulcrum. Example: garden shovel.
How does the position of the load or effort affect mechanical advantage in levers?
The mechanical advantage is greater if the load is closer to the fulcrum in Class One and Two Levers, and if the effort is closer to the load in Class Three Levers.
work =?
force x displacement
How to calculate mechanical advantage
MA= Output force/Input force
how is the number of ropes used to lift the object relate to mechanical advantage of the pulley
Mechanical advantage =number of ropes used to lift the object
Work of output side=work of input side
T/F
TRUE
What is a pulley and how does it work?
A pulley is a wheel with a groove and a rope in the groove, used to lift or lower heavy objects by changing the direction of the applied force.
