Charges arising from frictional contact
{"Image DocumentName": "Charges arising from frictional contact", "Image ImageDescription": "Physical Pharmacy 2. 4/15/2017. Charges arising from frictional contact. For a charge that arises from frictional contact, the empirical rule of Coehn states that: substance having a high dielectric constant (d.c.) is positively charged when in contact with another substance having a lower dielectric constant. E.g. most o/w emulsions stabilised by non-ionic surfactants are negatively charged \u2013 because water has a higher d.c. than oil droplets. At 25oC and 1 atm, the d.c. or relative permittivity for water is 78.5; for benzene ca Physical Pharmacy 2. KBA.", "Image XResolution": "37", "Image YResolution": "37", "Image ResolutionUnit": "Pixels/Centimeter", "Image Software": "SlidePlayer", "Image YCbCrPositioning": "Centered"}