Find the speed of a 4 fC charged particle with a mass of 5 pg after it travels 4

Question

Find the speed of a 4 fC charged particle with a mass of 5 pg after it travels 40 cm starting from rest in an electric field that increases linearly with position along the direction of motion such that its proportionality to distance is 2 kN/Cm. Ignore the force of gravity. What quantity of work must be done to assemble five identical particles of charge Q into positions on the points of an equilateral hexagon of side length w? The particles start from infinity. Answer in terms of k_E. Calculate the total quantity of work to bring a -100 nC particle from a starting distance of 0.8 m to an ending distance of 0.4 m from an infinite, straight line of charge with a uniform linear density of 12 pi mC/m through an inviscid gaseous substance with a permittivity of 3 times 10^-10 C^2/N middot m^2. Find a general expression for the work necessary to expand a uniform spherical surface charge sigma of radius r until it has twice the diameter while centered on the same point. Answer in terms of the permittivity.

Explanation / Answer

1)Given,

q = 4 fC = 4 x 10^-15 C ; m = 5 pg = 5 x 10^-12 g = 5 x 10^-15 kg ;

d = 40 cm ; E = 2 kN/Cm = 2 x 10^3 N/C

The charged particle will be under the influenec of force due to electric field.

F = q E

Work done in travelling d = 40 cm = 0.4 m

W = F d = q E d

This work is equal to the kinetic energy of the particle.

KE = W

1/2 m v^2 = q E d

v = sqrt (2 q E d/m)

v = sqrt (2 x 4 x 10^-15 x 2 x 10^3/(5 x 10^-15)) = 56.57 m/s

Hence, v = 56.57 m/s

Related Questions

Navigate

• Browse (All)
• Browse F
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.