5.3 Electric Field Strength An electric field is a region of space in which a charged object is acted upon by a force. The electric field shows the direction that a small positive test charge would move in a region of an electric field. p. 178 What is a Field? Positive ChargeNegative Charge 5.3 Electric Field Strength Electric Fields around pairs of Point Charges: p. 178 Uniform Electric Field between two oppositely charged plates: 5.3 Electric Field Strength Defining Electric Field p Electric Field Strength is defined as electric force per charge. E = FeFe Q {Units: N/C} Magnitude of Electric Field around a Source Charge Bringing electric force into the equations gives you: E = kQ R2R2 F e = k Q 1 Q 2 r2r2 5.3 Electric Field Strength Multiple Charges Creating Electric Fields: p. 183 The electric fields created by 2 or more charges are dealt with by adding the individually electric fields as vectors. P +q 1 +Q 2 E1E1 E2E2 E net = E 2 E 1 (At point P) 5.3 Electric Field Strength Key Questions In this section, you should understand how to solve the following key questions. Page 181 Practice Problem 5.3.1: #2 Page 182 Quick Check #3 Page 181 Practice Problem 5.3.2: #2 Page Review 5.3 #2,4,6,8, & 10