Electromagnetism qs need someone to check my work

[crosbykins]

Homework Statement

An electron is accelerated horizontally from rest in a television picture tube by a potential difference of 10,000 V. It then passes between two horizontal plates 5.0 cm long and 1.0 cm apart which have a potential difference of 200 V. At what angle θ will the electron be traveling after it passes between the plates?

Homework Equations

-ΔEE = ΔEK

The Attempt at a Solution

-ΔEE = ΔEK
qΔV = 1/2mv^2
√ (2qΔV)/(9.1*10^-31kg) = v
√ (2(1.6*10^-19 C)(10 000V))/ (9.1*10^-31kg) = v
5.9*10^7m/s = v

Δt = .06m/5.9*10^7 m/s
= 1.0*10^-9 s

acceleration = qv/md
= [(1.6*10^-19 C)( 5.9*10^7m/s)]/[(9.1*10^-31kg)(.01m)]
= 3.5*10^15 m/s^2

v2 = a Δt
= (3.5*10^15 m/s^2)( 8.5*10^-10 s)
= 3.5*10^6 m/s


θ = tan-1 [(3.5*10^6 m/s)/( 5.9*10^7m/s)]
= 3.4


The electron will be traveling at an angle of 3.4.

***is this right?

 

[ojs]

Don't you find it strange that you never use the 200V potential difference in your calculations?

I don't think that this answer is correct, I have not calculated it but the absence of the 200V and how you calculate your acceleration rings warning bells for me. Can you see what equation you should use to calculate the acceleration (think about in what direction is the acceleration of the electron)?