Quick acceleration word problem

AI Thread Summary
An electron with an initial speed of 3.0 x 10^5 m/s accelerates at 8.0 x 10^14 m/s² and needs to reach a speed of 5.4 x 10^5 m/s. The time required to achieve this speed is calculated to be 3 x 10^-18 seconds, although this value appears excessively large given the acceleration. To find the distance traveled during this time, the discussion suggests using one of the equations for motion with constant acceleration. Participants emphasize the importance of correctly applying the relationship between change in velocity, acceleration, and time. The conversation highlights the need for careful arithmetic and understanding of motion equations to solve for distance.
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Homework Statement


An electron has an initial speed of 3.0 x10^5 m/s. It undergoes an acceleration of 8.0 x 10^14 m/s/s. (a) How long will it take to reach a speed of 5.4 x 10^5 m/s? (b) How far will it have traveled in this time?


Homework Equations



Rate x Time= Distance



The Attempt at a Solution



A. R x T= D

(8.0 x 10^14 m/s/s)(T)=(5.4 x 10^5 m/s)-(3.0 x10^5 m/s)

T= 3x10^18 seconds

B. How do you find the distance traveled? This is stumping me for some reason.


Thanks!
 
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Assuming the magnitude of acceleration is correct, that's a huge acceleration.

The T should be quite small.

What is the relationship between the change in velocity, acceleration and time?
 
Joe has the correct relation, even if the terminology is a bit odd ("Distance" is really change in velocity, "Rate" is acceleration). He just needs to carefully redo the arithmetic given by that relation.

Part B: your textbook has 3 or 4 equations for motion with a constant acceleration. Look over them, and choose one which can be solved for distance using the given information.
 
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