Part A:What must the charge (sign and magnitude) of a particle of mass 1.48 g be
ID: 1871520 • Letter: P
Question
Part A:What must the charge (sign and magnitude) of a particle of mass 1.48 g be for it to remain stationary when placed in a downward-directed electric field of magnitude 650 N/C ?
Use 9.81 m/s2 for the magnitude of the acceleration due to gravity.
Part B: What is the magnitude of an electric field in which the electric force on a proton is equal in magnitude to its weight?
Use 1.67×1027 kg for the mass of a proton, 1.60×1019 C for the magnitude of the charge on an electron, and 9.81 m/s2 for the magnitude of the acceleration due to gravity.
Explanation / Answer
Part A)
Given that electirc field is downward ,so to remain the particle stationary,the electric Force must be balanced by gravitational force
Electric force = gravitational force
q*E = m*g
q = (m*g)/E = (1.48*10^-3*9.81)/650 = 2.24*10^-5 = 22.4*10^-6 C
sign is negative
so q = -22.4*10^-6 C
Part B) Electric force = weight
q*E = m*g
1.6*10^-19*E = (1.67*10^-27*9.81)
E = 1.02*10^-7 N/C