Question
Questions 14-15?
A 5 mu C charge is uniformly distributed on a ring of radius 12 cm. Find the electric field on the axis at 0.9 cm from the center of the ring. The value of the Coulomb constant is 8.99 times10^9 N middot m^2/C^2. Answer in units of N/C. Find the electric field on the axis at 3.3 cnm from the center of the ring. Answer in units of N/C. Find the electric field on the axis at 3.5 m from the center of the ring. Answer in units of N/C. Find the electric field on the axis at 3.5 nm assuming that the ring is a point charge at the origin. Answer in units of N/C. An electron and a proton are each placed at rest in an electric field of 218 N/C. What is the velocity of the electron 63.1 ns after being released? Consider the direction parallel to the field to be positive. The fundamental charge is 1.602 times 10^-19 C, the mass of a proton is 1.67267 times 10^-27 kg and of an electron 9.109 times 10^-31 kg. Answer in units of m/s.
Explanation / Answer
Q14. part 4 of 4
From Coulomb's law,
E = kq/r^2
= (8.99*10^9*5*10^-6)/(3.5)^2
= 3669.38 N/C (or 3.7*10^3 N/C rounded off)
Q15.
E = 218 N/C
t = 63.1 ns = 6.31*10^-8 s
a = qE/m
v = qEt/m
= -(218*1.6*10^-19*6.31*10^-8)/(9.10939*10^-31)
= -2.42*10^6 m/s
