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Two particles, an electron and a proton, are initially at rest in a uniform electric field of magnitude 506 N/C. If the particles are free to move, what are their speeds (in m/s ) after 44.4 ns ?

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Final answer:

The proton's speed after 44.4 ns is approximately 216.8 m/s, while the electron's speed is approximately -3.98 x 10^12 m/s.

Step-by-step explanation:

In a uniform electric field, particles experience a constant force that accelerates them. The force experienced by a charged particle in an electric field is given by the equation F = qE, where F is the force, q is the charge of the particle, and E is the electric field strength. Since the electron and proton have opposite charges, the direction of their forces will be opposite.

  1. First, let's calculate the force on the proton. Given that the electric field strength is 506 N/C, and the charge of a proton is 1.6 x 10^-19 C, we can calculate the force as:

F = qE = (1.6 x 10^-19 C)(506 N/C) = 8.16 x 10^-17 N

  1. The acceleration of the proton can be calculated using the equation F = ma, where F is the force, m is the mass of the object, and a is the acceleration. The mass of a proton is approximately 1.67 x 10^-27 kg.

F = ma = (1.67 x 10^-27 kg)(a)

a = F / m = (8.16 x 10^-17 N) / (1.67 x 10^-27 kg) ≈ 4.89 x 10^9 m/s^2

  1. Similarly, we can calculate the force on the electron:

F = qE = (-1.6 x 10^-19 C)(506 N/C) = -8.16 x 10^-17 N

  1. And the acceleration of the electron:

a = F / m = (-8.16 x 10^-17 N) / (9.11 x 10^-31 kg) ≈ -8.96 x 10^13 m/s^2

  1. The speeds of the particles after 44.4 ns can be calculated using the equation v = u + at, where v is the final velocity, u is the initial velocity, a is the acceleration, and t is the time.

Since the particles are initially at rest, their initial velocities (u) are 0 m/s. Therefore, the final velocities (v) can be calculated as:

  1. Final velocity of the proton:

v = u + at = 0 + (4.89 x 10^9 m/s^2)(44.4 x 10^-9 s) ≈ 216.8 m/s

  1. Final velocity of the electron:

v = u + at = 0 + (-8.96 x 10^13 m/s^2)(44.4 x 10^-9 s) ≈ -3.98 x 10^12 m/s

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