PULLEY:  A pulley is a grooved wheel that has a rope, belt or cable attached and can be used  to move things up, down, or across.

 

Objectives:

Student will be able to: identify a pulley as a wheel that turns on a rope, make a pulley and explore how it can be used to make work easier by lifting things.

Materials:

• Science Journal

• a piece of string 60 cm (2 feet) long

• clear adhesive tape

• some heavy books

• 1 m (3ft.) of ribbon  (wide enough to fit snuggly between the rims of the thread spool)

• a small empty thread spool

• a plastic bucket (such as a child's sand pail)

• small objects to lift

Procedure:

• Thread the string through the center hole of the thread spool.

• Tape the ends of the string to a table top so that the spool hangs about 10 cm (4inches) below the table's edge.  Use heavy books to hold the string ends in place.

• Tie one end of the ribbon to the handle of the bucket

• Slide the free end of the ribbon over the thread spool.  Slowly pull down on the free end.  Observe what happens to the bucket.

• Place small objects in your bucket elevator.  Try lifting them.

Journal:

• Record your results

• Draw and interpret results