Solving Gauss' Law Electromag Question w/ 100V Battery

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The discussion focuses on solving a physics problem involving a 100V battery connected to parallel plates, creating an electric field of 10^4 NC^-1. The force on an electron in this field was calculated as -1.6x10^-15 N, which is significantly greater than its weight of 8.94x10^-30 N, indicating the electron will move upward due to the electric field. For the second part of the problem, the user seeks guidance on deriving the trajectory of the electron projected with an initial horizontal velocity, comparing it to projectile motion. The suggestion is to apply projectile motion formulas to determine the electron's path, considering its unique upward movement in the electric field. Understanding these principles will help in accurately modeling the electron's trajectory.
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Electromag Question

Homework Statement



When the terminals of a 100V battery are connected to two large parallel horizontal plates 1 cm apart the electric field E between them has a magnitude of E=10^4 NC^-1, and is directed upward. Compute the force on the electron in the field and compare it with the weight of the electron.

[charge on an electron = -1.6x10^-19, mass of electron =9.11x10^-31kg]

If the electron were projected into the field with an initial horizontal velocity V0, find the equation of its trajectory of the form y=f(x) (take y verticle and x horizontal).


The Attempt at a Solution



I have a solution to the first part using the formula: F=qE, I found f = -1.6x10^-15.
I then wored out the weight using w=mg, getting 8.94x10^-30 N. I compared this and explained that as F is vastly bigger than W the object will move upwards rather than downwards towards gravity.

However I have no clue on how to do the second part, please help.
 
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This is just like throwing a ball horizontally, and asking for the path it follows (except the electron "falls" up, because of the electric field). Just look up all those formulas from mechanics.
 
So are you basically saying I should use the projetile motion formulas?
 
Thread 'Variable mass system : water sprayed into a moving container'

Thread 'Variable mass system : water sprayed into a moving container'

Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
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