GUIDED DISCOVERY LESSON
"Incline Planes"
Unit: Force and Motion
Background: Students explore the mechanical advantage of a ramp by measuring the change in force required to pull a mass to the top of a ramp.
Learning Objectives:
Students will construct a ramp using LEGO elements.
Students will collect data to compare the mechanical advantage to effort.
Students will make generalizations that they can apply to determine
the mechanical advantages.
Learning Standards:
State Goal 12: Understand the fundamental concepts, principles
and interconnections of the life, physical and earth/space sciences.
D. Know
and apply concepts that describe force and motion and the principles that
explain them.
Materials:
LEGO elements (per group)
* 1 base plate
* 2 1 x 16 beams
* 2 1 x 12 beams
* 2 1 x 8 beams
* 2 1 x 6 beams
* 2 1 x 4 beams
* 1 2 x 4 brick
* 1 2 x 4 plate
* 2 connector pegs
* 1 bushing
* 1 weighted brick
Investigation Tools
Spring scale (250 grams or 2.5 newtons)
String
Ramp (ruler, paint stick, etc.)
Tag board
Tape
Learning Activities:
Motivation
To promote inquiry as to why things work the way
they do and with the help of simple machines like the
incline plane.
Data Collection
The students will construct a ramp and make predictions
and inferences by adjusting the angle of the
and using a spring scale to measure the force.
The standard axle position for the ramp will be set for data comparison.
The students will be encouraged to work in pairs for the entire activity recording information on their separate activity pages.
Data Processing
After the students have completed their three different
trials for each ramp position have them record their data each
time to determine the most and least effort of the
ramps, the amount of force used and the amount of force needed to lift
an object up the ramp.
The students will test their predictions, graph
the effort of force for each position and will be allotted time to calculate
the
mechanical advantage.
Closure
The students will analyze and discuss
their findings with the entire class. We will discuss the comparison of
the mechanical
advantage to the effort, explore what the
mechanical advantage tells us, the patterns in the graphs and allow the
students
to go around to find other pairs that have
similar and different graphs.
Assessment and Evaluation
The students will be observed by the teacher for participation
points and their activity sheets will receive a letter
grade.