Levers
How many classes of levers are there?
3 classes.
What is a pulley?
A wheel with a groove and a rope. It is used to pull objects up with ease.
What is an axle?
A rod that attaches the wheel to the object. It turns the wheel.
What is an inclined plane?
A flat surface tilted at an angle. Also called ramp.
What is a screw?
It is a spiral wrapped around a center post. When you turn it, it can lift two objects or hold them together.
What class of lever is a wheelbarrow?
A second class lever
What kind of lever is a fixed pulley?
1st class.
What is 1 difference between a wheel and a roller?
- Wheel is smaller
- Wheel has an axle
- Wheel is easier to control
What can we use an inclined plane for?
Loading things into the back of a truck, using to get up for people in wheelchairs, walking upwards.
Screws turn rotational movement into what?
Linear movement.
How do I make a first class lever easier to use?
I bring the fulcrum closer to the load.
What is 1 example of a pulley?
Blinds, a crane, a well.
Name 1 object that has wheels and an axle on it?
Cars, grocery carts, skateboard, etc.
What is an example of an inclined plane?
Slide, stairs, ramp, hills.
Does a water bottle have a screw?
Yes.
Which lever am I describing? The fulcrum is on one side, the effort is in the middle and the load is on the opposite side.
3rd class.
What is the difference between a fixed and movable pulley?
A fixed pulley is stuck to a roof or hard surface and a movable pulley is in the middle of a rope and can move.
When the wheel and axle move what part has the smallest movement?
The axle.
How does an inclined plane work?
It takes the weight of the object, making it easier for us to move it up the ramp.
What is a wedge
It is two inclined planes that are back to back. It is used to force things apart.
Name a body part that is a lever and tell me which parts would be the fulcrum, the load, and the effort.
Arm: Muscle is the effort, weight is the load, and elbow is the fulcrum.
What type of lever is a movable pulley?
2nd class.
Is a can a wheel or a roller? Why?
Using objects around you make an inclined plane.
Name an example of a wedge.
An axe, a spatula, a crowbar.