How Is the Mass of a Charged Particle Determined in an Electric Field?

AI Thread Summary
To determine the mass of a positively charged particle suspended in an electric field, the relationship between force, charge, and electric field strength must be considered. The particle's charge is given as 9.35 pC, and the electric field is generated by two charged plates. The participant initially calculated the mass using the charge-to-proton mass ratio but arrived at an incorrect value. The correct approach involves equating the electric force (F = qE) to the gravitational force (F = mg), leading to the formula m = (q/g) * |E|. This method clarifies the calculation, resulting in the correct mass of 4.9 x 10^-4 kg.
adca14
Messages
11
Reaction score
0

Homework Statement


A positively charged particle (9.35pC) is suspended in equilibrium in an electric field between two horizontal parallel plates with opposite charges. Each one of the square plates has a charge of 5.5x10^-5C; and are separated by 6.25mm and their sides are 11cm long
what is the mass of the particle?

Homework Equations


E=kq/r^2
n=q/qp
idk...

The Attempt at a Solution


first i divided the charge of the particle by the elemental charge
9.35x10^-12/1.602x^-19
i got 58364544
then i multiplied this number by a protons mass
58364544*(1.673x^-27)
i got 9.764x10^-20

the book says the answer is 4.9x10^-4
soo confused!
 
Physics news on Phys.org
Consider the E-Field between the plates.

What does that come to?

You know that F = q*E

And you also know F = m*g

So ...

m = (q / g) * |E|
 
wow, i feel like a moron for not seeing that! thanks!
 

Thread 'Rolling without slipping on a curved surface'

Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
View full post »
Thread 'Trying to understand the logic behind adding vectors with an angle between them'

Thread 'Trying to understand the logic behind adding vectors with an angle between them'

My initial calculation was to subtract V1 from V2 to show that from the perspective of the second aircraft the first one is -300km/h. So i checked with ChatGPT and it said I cant just subtract them because I have an angle between them. So I dont understand the reasoning of it. Like why should a velocity be dependent on an angle? I was thinking about how it would look like if the planes where parallel to each other, and then how it look like if one is turning away and I dont see it. Since...
View full post »
Thread 'Correct statement about a reservoir with an outlet pipe'

Thread 'Correct statement about a reservoir with an outlet pipe'

The answer to this question is statements (ii) and (iv) are correct. (i) This is FALSE because the speed of water in the tap is greater than speed at the water surface (ii) I don't even understand this statement. What does the "seal" part have to do with water flowing out? Won't the water still flow out through the tap until the tank is empty whether the reservoir is sealed or not? (iii) In my opinion, this statement would be correct. Increasing the gravitational potential energy of the...
View full post »

Similar threads

Same Charge, Same Mass? | Subatomic Particles
Replies
28
Views
2K
The electric potential inside a conducting sphere with charge Q
Replies
11
Views
2K
Find net velocity of charged particle in electric field (symbols only)
Replies
14
Views
3K
Direction of electric field vector on the surface of charged conductor
Replies
9
Views
2K
Question about charged particle in an electric field
Replies
5
Views
2K
Sheet of charge - theory
Replies
1
Views
952
Electric Field for the circular path of a positively charged particle
Replies
3
Views
3K
I Thought I Understood Gauss' Law (Sheets)
Replies
26
Views
2K
Two charged beads with a third bead in equilibrium
Replies
32
Views
3K
Electric Potential slowing a charged particle to a stop
Replies
4
Views
3K

Hot Threads

Recent Insights

Back
Top