Simple Machines
Name 2 of the 6 simple machines
What is a force
push or pull
What type of force is used in a pulley
Pull
What is a gear
a toothed wheel
What is rotary motion?
motion in a circular motion
Why is a ramp considered a simple machine
it makes it easier to move objects up and down
if you push a ball harder, what happens to its speed? Why?
it goes faster because more force is applied to it
What type of pulley is this - *Miss Morrison will show picture
fixed pulley
Why do gears have teeth (2)
to connect and transfer motion
why is a wheel an example of rotary motion?
it spins in a circle
you need to lift a heavy box into a truck. Which simple machine would help most and why?
Inclined plane, reduces effort as it helps slide the heavy object up and down
why is direction important when applying a force?
it determines where the object will move to
where might you see a pulley in real life and why is it used there?
flagpole, blinds, crane - to lift/ move easier
List the 5 types of gears and explain 1 of them
spur gear, crown gear, idler gear, worm gear, bevel gear
give an example of something that changes from rotary to linear motion
Bike - pedals rotate, chain moves straight
screw or drill - rotating motion - moves forward into material
conveyor belt - rollers rotate - belt moves straight
wind up toys - turning key - parts move in straight line
a knife and an axe are both wedges. How do they make work easier?
They split/ cut by pushing material apart
pedals, chain, gears, wheels
Out of both pulleys, which pulley is doing less work and why? - *Miss Morrison to show pictures
the compound pulley because there are 2 pulleys being used
What 3 factors do gears influence? (3)
direction, speed, and force
why do machines need different types of motion
machines are able to perform many different tasks in many different directions
Two students are moving the same heavy object. one uses a ramp and one lifts it straight up. Who is using less force? Explain why
the student using the ramp - it spreads the work over a longer distance
what would happen if one part of a mechanism stopped working?
the system may fail or not work properly
In a moveable pulley - where is the load attached?
the load is directly attached to the wheel
*refer to Miss Morrison for picture - Which gear would turn with more force?
the second gear
How can machines both help and harm the environment
reduce work, build things, pollution and energy use