Maximum initial speed the electron can have without hitting the negative plate

AI Thread Summary
The discussion centers on calculating the maximum initial speed of an electron launched at a 45-degree angle from a positive plate, given a distance of 2.0 cm between two parallel plates and an electric field strength of 1.0 × 10^4 N/C. One participant suggests that the maximum speed is 1.3 × 10^7 m/s and seeks confirmation. Another contributor emphasizes the importance of showing work for verification, detailing the calculations involving acceleration and the relationship between vertical and initial speeds. The calculations confirm that the maximum initial speed is indeed approximately 1.3 × 10^7 m/s. The conversation highlights the need for clear problem-solving steps in physics discussions.
kirby2
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Two parallel plates are 2.0 cm apart and the electric field strength between
them is 1.0 × 10^4 N/C. An electron is launched at a 45 degree angle from the
positive plate. What is the maximum initial speed v0 the electron can have
without hitting the negative plate?

i think the answer is 1.3x10^7 m/s. can someone confirm this?
 
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kirby2 said:
Two parallel plates are 2.0 cm apart and the electric field strength between
them is 1.0 × 10^4 N/C. An electron is launched at a 45 degree angle from the
positive plate. What is the maximum initial speed v0 the electron can have
without hitting the negative plate?

i think the answer is 1.3x10^7 m/s. can someone confirm this?

It would be much easier for us to confirm it if you posted your work for us to see. Remember, that's part of the PF rules -- posting your attempt at the solution.
 
The acceleration = F/m = E*q/m

So at y max vy = 0 so

vy^2 = vy0^2 - 2*E*q/m*ymax

So vy0 = sqrt(2*E*q/m*ymax) = sqrt(2*1.20x10^4*1.60x10^-19/9.11x10^-31… = 9.18x10^6m/s

So v0 = vy0/sin(45) = 9.18x10^6m/s/sin(45) = 1.30x10^7m/s
 
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