Simple Machines

Jensen, Tom Bloom High School

Objectives 1) Student will see a large number of everyday items in terms of simple machines i.e. levers,inclined planes, wheels and axles. 2) Student will experience the use of and see demonstrations of simple machines. 3) Student should discover that simple machines reduce the effort required in a task,not the total work. 4) Student will see physics as a part of everyday life. Equipment and Materials Variety of simple machines in the classroom or laboratory. (Door handles and hinges etc...) Simple machines brought from home or work by each student. Recommended Strategies Several days before the simple machines activity, assign each student in class to
bring a simple machine on the assigned day. On each successive day remind the
students of their assignment and tantalize them with some "prize" for the best and/or
most unique simple machine. Create an atmosphere of suspense concerning the "prize"
as well as curiosity and interest concerning simple machines. Get them ready.

On the day of the simple machine activity start by demonstrating some simple tools
such as a hammer and nails, pliers etc... (Hammer a nail into a piece of wood with a
ball-peen hammer, then try to remove the nail, make a point of the difficulty
encountered, and seek suggestions from the class.) After a few sample machines (from
tool box and/or kitchen) ask each student individually to show the machine brought to
class. The student should categorize the machine (lever, inclined plane) and tell,
and demonstrate if possible, its uses. The more unusual items will usually stimulate
comments and discussion which must be controlled as time permits.

Often students will forget or not bother to bring any machine. That is their problem.
This may be turned into a very positive and creative learning situation. Allow such
students to find a machine in the room or among their personal belongings. This is
often the best part of the entire activity and under "pressure" machines such as
keys, pencils, mechanical pencils, lipstick tubes, compacts, window shade rollers,
and an endless supply of machines is created.

As the students present the machines, it might be a good idea to comment on such
things as effort vs. work, what the machine is used for, and possible alternatives
that might work better.

As the activity is concluded the "winner" is chosen by vote of the class or chosen by
the instructor. The "prize" might be a simple machine such as a pop top (lever) with
a can of coke attached to it.

Such an activity must be adjusted to grade level, class size (large classes may bring
one machine per C.L. group) and time constraints. The activity may by followed with
other activities such as lab exercises to quantify the relationship between effort
and work, and incorporate concepts such as efficiency and mechanical advantage.

Always emphasize objective #4 to foster an appreciation for, and allay fears of
SCIENCE and science classes.

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