Register to reply 
Guassian infinite sheet and charge with kinetic energy 
Share this thread: 
#1
Jun908, 11:57 PM

P: 160

1. The problem statement, all variables and given/known data
two infinite sheets of charge (one positive, one negative) are arranged parallel to each other and separated by a distance of 2m. a charge of 3 microcoulombs is realeased at the positive plate. when it reaches the negative plate it has a kinetic energy of 0.6 joules. what is the electric field between the plates 2. Relevant equations electric field of charge sheet E = sigma/2(epsilon_o) where sigma = charge density, epsilon_o = constant 8.85*10^12 energy U = 1/2 CV^2 where C is capacitance, v is electric potential C = Q/V where Q is charge, V is electric potential 3. The attempt at a solution do i assume sigma as constant? do i assume both sheets have the same electric field, so electric field between the sheets is the sum of the two? how does the energy play a role in determining the electric field, the equation for electric field is already specified, and can be solved in terms of constants, assuming sigma is constant too. if i use the energy and capacitance equation i get: U = 1/2[(Q/V)(V^2)] 0.6 = QV/2 i am not sure how Q, V relate to electric field, i'm lost actually... help appreciated 


#2
Jun1008, 12:18 AM

Sci Advisor
HW Helper
Thanks
P: 25,228

Yes, yes. Constant sigma. Constant E field. Now start throwing out equations you don't need. Don't stop too soon. You only need one.



#3
Jun1008, 07:30 AM

P: 160

still somewhat lost, i did find in actuality that using :
U = 1/2[(Q/V)(V^2)] 0.6 = QV/2 V = 400000 volts when Q = +3*10^6 coulombs but how does V relate to electric field E? 


#4
Jun1008, 09:25 AM

Sci Advisor
HW Helper
Thanks
P: 25,228

Guassian infinite sheet and charge with kinetic energy



Register to reply 
Related Discussions  
Electric Field for infinite sheet of uniform charge per unit area  General Physics  10  
Calculating the Kinetic Energy of a Point Charge From Far Away  Introductory Physics Homework  0  
Kinetic Energy of a Charge  Introductory Physics Homework  0  
Kinetic energy of a charge  Introductory Physics Homework  4  
Infinite sheet of charge..just need help on sigma stuff  Introductory Physics Homework  3 