Four charges are placed at the four corners of a square of side 15 cm. The charges on the upper left and right corners are +3 μC and -6 μC respectively. The charges on the lower left and right corners are -2.4 μC and -9 μC respectively. The net electric force on -9 μC charge is:
a. 5.1 x1011 N/C away from the proton
b. 5.1 x1011 N/C toward the proton
c. 5.1 x1010 N/C toward the proton
d. 5.1 x1010 N/C away from the proton
is it towards the proton?
I think it will be away from the proton...
I didn't do the math.
To find the net electric force on the -9 μC charge, we need to calculate the electric forces exerted by each of the other charges and then add them together. The electric force between two charges can be calculated using Coulomb's Law:
F = k * |q1| * |q2| / r^2
where F is the electric force, k is the electrostatic constant (9 x 10^9 N m^2/C^2), q1 and q2 are the magnitudes of the charges, and r is the distance between the charges.
Let's calculate the electric forces:
1. Electric force between -9 μC and +3 μC:
F1 = k * |q1| * |q2| / r^2
= (9 x 10^9 N m^2/C^2) * (9 μC) * (3 μC) / (15 cm)^2
= 18 x 10^3 N/C away from the +3 μC charge (repulsive force)
2. Electric force between -9 μC and -6 μC:
F2 = k * |q1| * |q2| / r^2
= (9 x 10^9 N m^2/C^2) * (9 μC) * (6 μC) / (15 cm)^2
= 72 x 10^3 N/C away from the -6 μC charge (repulsive force)
3. Electric force between -9 μC and -2.4 μC:
F3 = k * |q1| * |q2| / r^2
= (9 x 10^9 N m^2/C^2) * (9 μC) * (2.4 μC) / (15 cm)^2
= 28.8 x 10^3 N/C away from the -2.4 μC charge (repulsive force)
The net electric force on the -9 μC charge would be the vector sum of these forces. Since all of the forces are repulsive and pointing away from the -9 μC charge, the individual forces can simply be added together:
Net force = F1 + F2 + F3
= 18 x 10^3 N/C + 72 x 10^3 N/C + 28.8 x 10^3 N/C
= 118.8 x 10^3 N/C
Therefore, the net electric force on the -9 μC charge is 118.8 x 10^3 N/C away from the proton.
None of the options provided match the correct answer.