Question

9. how many electrons must be added to a neutral obeject to provide it a charge of -2.4 uC?

10. as shown in the diagram, three equal Charges are spaced evenly in a row. The magnitude of each charge is +2e, and the distance between two adjacent charges is 1.5 nm. then the central check charge is displaced .350 nm to the right while the other two charges are held in place. after the displacement what is the magnitude and direction of the net force that the outer two charges exert on the central charge?

9. How many electrons must be added to a neutral object to provide it a charge of -2.4 uC? (l pont) 02.4 x 1013 electrons 0 1.5 x 1013 electrons 04.8 x 1012 electrons 6.7 x 1014 electrons 10. As shown in the diagram, three equal charges are spaced evenly in a row. The magnitude of each charge is +2e, and the distance between two adjacent charges is 1.50 nm. Then the central charge is displaced 0.350 nm to the right while the other two charges are held in place. After the displacement, what is the magnitude and direction of the net force that the outer two charges exert on the central charge? 150 n 1.50nm +2e +2e +2e

Answer 1

(9) A single electron has -1.602 x 10^-19 C charge.

So, for charge , we need

A single electron has -1.602 times 10^-19 C charge. So, for -2.4 mu C charge, we need -2.4 times 10^-6/-1.602 times 10^-19 = 1.5 times 10^13 electrons. Given, magnitude of each charge is + 2e = 2 times 1.602 times 10^-19 = 3.204 x 10^-19 C. The electrostatic force between two charged particles having charge ' q ' and ' Q ' and separated by a distance r is given by F = 1/4 pi E_0 qQ/r^2 where, 1/4 pi E_0 = 9 times 10^9 Nm^2/C^2 Here, F_A is force on the charge at B (displaced charge) due to the charge at A (charge in the left side). F_B is force on the charge at B (displaced charge) due to the charge at C (charge in the right side). The direction of forces are shown in the diagram (same charges repel each other).So, F_A = 1/4 pi E_0 2e times 2e/AB^2 = 9 times 10^9 times 4e^2/(AO + OB)^2 = 9

   electrons.

(10) Given , magnitude of each charge is +2e = 2 x 1.602 x 10^-19 = 3.204 x 10^-19 C .

The electrostatic force between two charged particles having charge ' q ' and ' Q ' and separated by a distance r is given by

  

Where,   

Here, $F_{A}$ ​ is force on the charge at B (displaced charge) due to the charge at A (charge in the left side).

   $F_{B}$   is force on the charge at B (displaced charge) due to the charge at C (charge in the right side).

the direction of forces are shown in the diagram (same charges repel each other).

So,

  

  

  

     

   (acting towards the right )

And

  

  

  

     

   (acting towards the left )

So, the net force will be

   (acting towards the left)

  

  (acting towards the left)

Hence, the correct option will 4.27 x 10^-10 N towards the left.

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