Help Needed: Calculating Mass/Charge Ratio & Carbon Atom Count

[physics.student]

Hi I am just having trouble figuring out this question. If someone can help me out it would be greatly appreciated

The imaging drum of a photocopier is positively charged to attract negatively charged particles. Near the surface of the drum, its electric field has a magnitude of 1.40 * 10^5 N/C. A toner particle is to be attracted to the drum with a force that is ten times the weight of the particle.

What is the ratio of the mass of a toner particle to the magnitude of its net charge?

If the toner particles are made of carbon, how many carbom atoms are there for each excess electron on a toner particle?

 

[Nate810]

The ratio of the mass of a toner particle to the magnitude of its net charge is not possible to calculate without additional information. If the toner particles are made of carbon, there would be 6 x 10^23 carbon atoms for each excess electron on a toner particle.

 

[m2003]

I am happy to assist you with these calculations. In order to calculate the mass/charge ratio of the toner particle, we will need to use the equation F = qE, where F is the force, q is the charge, and E is the electric field. We know that the force is ten times the weight of the particle, so we can set up the equation as 10mg = qE, where m is the mass of the particle and g is the acceleration due to gravity. We also know that the electric field has a magnitude of 1.40 * 10^5 N/C. Therefore, we can rearrange the equation to solve for the mass/charge ratio, which is m/q = 10g/E.

To calculate the number of carbon atoms for each excess electron, we will need to use Avogadro's number, which is 6.022 * 10^23 atoms/mol. We can set up the equation as n = q/e, where n is the number of moles of electrons, q is the charge, and e is the charge of an electron (1.602 * 10^-19 C). Since we know the charge of the toner particle from the previous calculation, we can solve for the number of moles of electrons. Then, we can use the molar mass of carbon (12.01 g/mol) to convert from moles to grams. Finally, we can divide the mass of the toner particle (calculated in the previous step) by the mass of one carbon atom (12.01 g) to determine the number of carbon atoms present.

I hope this helps you with your calculations. If you have any further questions, please let me know. Remember to always double check your calculations and units to ensure accuracy. Good luck!