Vertical displacement of electron

[willson.slp]

Homework Statement

An electron with a speed of 1.9 × 107 m/s moves horizontally into a region where a constant vertical force of 4.3 × 10-16 N acts on it. The mass of the electron is 9.11 × 10-31 kg. Determine the vertical distance the electron is deflected during the time it has moved 34 mm horizontally.
(btw the answer is in meters)

Homework Equations

F=ma
a=F/m

x-x.o=v.ot+(1/2)a*t^2
y-y.o=v.o yt-(1/2)at^t

The Attempt at a Solution

I've gotton completely lost on this. First I solved for acceleration and got 4.72E14 m/s^2. Next I used that to find time using the horizontal displacement formula and got t=1.20027E-8. When i plugged all that into find the vertical displacement I got .034meters which was incorrect. I ve tried a few other ways but to no avail. Any help would be great.

Thanks

 

[ideasrule]

Your method is correct, but t is not equal to 1.20027E-8 s. What value did you use for "a" in the horizontal displacement formula? It should be 0 because there's no horizontal force.

 

[willson.slp]

When I used a=F/m I got (4.3E-16)/9.11E-31) which equals 4.72E14

when I try a=0 in the horzizontal displacement formula, I got t= .000002

Do I use that in the vertical diplacement formula for t and then 4.72E14 for a?

 

[Redbelly98]

When I used a=F/m I got (4.3E-16)/9.11E-31) which equals 4.72E14

when I try a=0 in the horzizontal displacement formula, I got t= .000002

There are two problems with that answer:
1. Did you use 34 m or 34 mm for the horizontal distance?
2. Your answer has just 1 significant figure, but it should have 2 significant figures.

Do I use that in the vertical diplacement formula for t and then 4.72E14 for a?

Yes, once you get the correct value of t, use it and 4.72e14 m/s². Important: what is the vertical component of the initial velocity?

 

[rwisz]

for your question! To solve this problem, we need to use the equations of motion to determine the vertical displacement of the electron. First, let's find the acceleration of the electron in the vertical direction using the formula F=ma. We know that the force acting on the electron is 4.3 × 10-16 N, and the mass of the electron is 9.11 × 10-31 kg. Plugging these values into the formula, we get:

a = F/m = (4.3 × 10-16 N)/(9.11 × 10-31 kg) = 4.72 × 1014 m/s2

Next, we can use the equation y-yo = vyo*t - (1/2)*a*t^2 to find the vertical displacement of the electron. We know that the initial velocity in the y-direction (vyo) is 0, since the electron is initially moving horizontally. We also know that the time (t) is 1.20027 × 10-8 s, as you calculated. Plugging in these values, we get:

y-yo = 0 - (1/2)*(4.72 × 1014 m/s2)*(1.20027 × 10-8 s)^2 = -3.22 × 10-17 m

This is a very small displacement, which makes sense since the electron is initially moving horizontally and the force acting on it is very small. Therefore, the vertical displacement of the electron during the time it has moved 34 mm horizontally is approximately 0 meters. I hope this helps!