Question

A student plans an investigation to show how charges are distributed on an insulator versus a conductor. The student wants to demonstrate that a metal coffee can is a conductor, and a plastic water pipe is an insulator. The following materials are available: a cloth made of wool flannel, a piece of plastic water pipe, a metal coffee can, an insulating rubber mat, a plastic rod, and aluminum foil strips suspended from a wire that has tape covering the part that he touches.



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The student writes down the first six steps in the plan:



Place the metal can on the insulated rubber mat.
Charge the plastic rod by rubbing it with the wool flannel cloth.
Touch several places on the metal can with the charged plastic rod.
See if the aluminum strips are attracted or repelled when brought near the container.
Record the results and switch containers on the mat.
Charge several places on the plastic water pipe by rubbing it with the wool flannel cloth.


Which TWO steps should be repeated after Step 6 to complete the experiment?



A.
Step 1

B.
Step 2

C.
Step 3

D.
Step 4

E.
Step 5

F.
Step 6

Answer 1

D and E.

After charging the plastic pipe (Step 6) you should again bring the aluminum strips near the container to observe attraction/repulsion (Step 4) and record those results (Step 5).