Two identical small metal spheres are separated by 1.00 × 105 m and exert an 18.9-N repulsive force on each other. A wire is connected between the spheres and then removed. The spheres now repel each other, exerting a 22.5-N force. Assume both charges are positive.

1. Determine the total charge of this system.
q =______ (units)

2. Determine the charges of the spheres before the connection.
q1, q2 = ______ C

Respuesta :

Answer:

(a). The total charge of this system is 10 C.

(b). The charges of the spheres before the connection is 5 C and 4.2 C.

Explanation:

Given that,

Distance [tex]r= 1.00\times10^{5}\ m[/tex]

Force = 22.5 N

The two spheres are connected for a moment by a wire. After this, charge is re-distributed equally, and each sphere now has a charge

We need to calculate the charge

Using formula of electric force

[tex]F=\dfrac{kq_{1}q_{2}}{r^2}[/tex]

Here, charge is equal

Put the value into the formula

[tex]22.5=\dfrac{9\times10^{9}\times q^2}{(1.00\times10^{5})}[/tex]

[tex]q^2=\dfrac{22.5\times(1.00\times10^{5})^2}{9\times10^{9}}[/tex]

[tex]q=\sqrt{\dfrac{22.5\times(1.00\times10^{5})^2}{9\times10^{9}}}[/tex]

[tex]q=5\ C[/tex]

(a). We need to calculate the total charge of this system

We have the charge of each sphere after re-distribution.

We know that the charge is distributed equally.

Therefore, the total charge of the system is

[tex]q+Q=2q=2\times5=10\ C[/tex]

(b). We need to calculate the charge of the spheres before the connection

Using formula of electric force

[tex]F=\dfrac{kq_{1}q_{2}}{r^2}[/tex]

Put the value into the formula

[tex]18.9=\dfrac{9\times10^{9}\times q_{1}\times q_{2}}{(1.00\times10^{5})}[/tex]

[tex]q_{2}=\dfrac{18.9\times(1.00\times10^{5})^2}{9\times10^{9}\times5}[/tex]

[tex]q_{2}=4.2\ C[/tex]

Hence, (a). The total charge of this system is 10 C.

(b). The charges of the spheres before the connection is 5 C and 4.2 C.

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