Contents
Cal Poly Pomona
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Physics Demonstrations at Cal Poly Pomona

Demo Index:
    EM-A-PN
Pira Index:
    5A 10.20
Title:
    POS. & NEG. ELECTROPHORUS
Description:
    Demonstrates the effects of like and unlike charges on an electroscope.
Equipment:
    1. Acrylic plate & charge disk w/handle
    2. PVC plate & charge disk w/handle
    3. Paper towel
    4. Electroscope
Procedure:
    CHARGING NEGATIVELY:
    1. Rub paper towel across acrylic to charge plate positively. Set charge disk on plate & touch metal disk with your finger. Lift disk (now negatively charged) by handle. Touch disk to knob of electroscope.

    CHARGING POSITIVELY:
    2. Rub paper towel over PVC plate to charge plate negatively & set charge disk on plate. Touch metal disk with your finger. Disk is now charged positively. Bring disk (positively charged) near the negative charged electroscope ((from step 1) Electroscope should show discharge.