Respuesta :
Answer:
F3 = 1.03 * 10⁻³ N : net force F3 acting on particle 3 due to the presence of the other two particles.
θ= -79.1° : direction of the net force F3
θ= 79.1° measured from the positive x axis ,clockwise
Explanation:
Theory of electrical forces
Because the particle q₃ is close to two other electrically charged particles, it will experience two electrical forces.
Equivalences
1nC= 10⁻⁹ C
Known data
k = 8.99*10⁹ N*m²/C²
q₁ = -8.7 nC = -8.7 * 10⁻⁹ C
q₂=-17.4 nC =-17.4 * 10⁻⁹ C
q₃= +8 nC= +8 * 10⁻⁹ C
d₁₃= 0.04 m
d₂₃= 0.04 m
d₁₃: distance from q₁ to q3
d₂₃: distance from q₂ to q3
Graphic attached
The directions of the individual forces exerted by q₁ and q₂ on q₃ are shown in the attached figure:
The force F₁₃ of q₁ on q₃ is attractive because the charges have opposite signs.
The force F₂₃ of q₂ on q₃ is attractive because the charges have opposite signs.
Calculation of the net force exerted for q₁ and q₂ on the charge q₃
The net force exerted for q₁ and q₂ on the charge q₃ is the algebraic sum of the forces in x-y of F₁₃ and F₂₃
Fn₃x =F₁₃x+ F₂₃x
Fn₃y = F₁₃y+F₂₃y
Calculation of the magnitudes of F₁₃ and F₂₃
To calculate the magnitudes of the forces exerted by the charges q₁, and q₂ on q₃ we apply Coulomb's law:
F₁₃=(k*q₁*q₃)/d₁₃²
F₁₃=(8.99*10⁹*8.7*10⁻⁹*8*10⁻⁹)/(0.04)² = 3.91*10⁻⁴ N
F₂₃=(k*q₂*q₃)/d₂₃²
F₂₃=(8.99*10⁹*17.4*10⁻⁹*8*10⁻⁹)/(0.04)² = 7.82*10⁻⁴ N
Calculation of the x-y components of F₁₃ and F₂₃
F₁₃x=F₁₃*cos60°= 3.91*10⁻⁴ N *cos60°= 1.955*10⁻⁴ N
F₁₃y=F₁₃*sin60°= 3.91*10⁻⁴ N *sin60°= 3.386*10⁻⁴ N
F₂₃x=F₂₃*cos60°= 7.82*10⁻⁴ *cos60°= 3.91*10⁻⁴ N
F₂₃y=F₂₃*sin60°= 7.82*10⁻⁴ *sin60°= 6.772*10⁻⁴ N
Calculation of the x-y components of Fn₃
Fn₃x = F₁₃x+F₂₃x= - 1.955*10⁻⁴ N + 3.91*10⁻⁴ N = 1.955*10⁻⁴ N
Fn₃y = F₁₃y+F₂₃y= - 3.386*10⁻⁴ N - 6.772*10⁻⁴ N = - 10.158 *10⁻⁴ N
Calculation of the magnitude of Fn₃
[tex]F_{n3} = \sqrt{(F_{n3}x)^{2} +(F_{n3}y)^{2} }[/tex]
[tex]F_{n3} = \sqrt{( 1.955*10^{-4})^{2} +( -10.158 *10^{-4})^{2} }[/tex]
F3=Fn₃= 1.034 * 10⁻³ N : net force F3 acting on particle 3 due to the presence of the other two particles.
Calculation of the direction (θ) of Fn₃
θ= tan⁻¹ (Fn₃y/Fn₃x)
θ= tan⁻¹ (- 10.158 *10⁻⁴ / 1.955*10⁻⁴ N)
θ= -79.1°
θ= 79.1° measured from the positive x axis, clockwise
The resultant magnitude of the electrostatic force is 1.034 × 10⁻⁴ and the angle of the resultant force is 10.89⁰.
What is an electrostatic force?
The electrostatic force is directly proportional to the product of the charges and inversely proportional to the square of the distance between them.
That is given as
[tex]\rm F \propto \dfrac{q_1q_2}{r^2}\\\\F = k \dfrac{q_1q_2}{r^2}[/tex]
Where k is a constant.
Three charged particles are placed at each of three corners of an equilateral triangle whose sides are of length 4.0 cm.
Two of the particles have a negative charge: q₁ = -8.7 n C and q₂ = -17.4 n C The remaining particle has a positive charge of 8.0 n C.
k = 8.99*10⁹ N*m²/C²
The force of attraction between q₁ and q₃ will be
[tex]\rm F_{13} = \dfrac{8.99*10^9 *8.7*10^{-9}*8*10^{-9}}{0.04^2}\\\\F_{13} = 3.91*10^{-4} \ N[/tex]
Similarly, the force of attraction between q₂ and q₃ will be
[tex]\rm F_{23} = \dfrac{8.99*10^9 *17.4*10^{-9}*8*10^{-9}}{0.04^2}\\\\F_{23} = 7.82*10^{-4} \ N[/tex]
The component of force along x-direction will be
[tex]\rm F_x = F_{13}*cos \ 60^o + F_{23}*cos \ 60^o\\\\F_x = - 3.91*10^{-4}*cos\ 60^o +7.82*10^{-4}*cos \ 60^o\\\\F_x = 1.955*10^{-4}[/tex]
The component of force along y-direction will be
[tex]\rm F_y = F_{13}*sin\ 60^o + F_{23}*sin\ 60^o\\\\F_y = 3.91*10^{-4}*sin\ 60^o +7.82*10^{-4}*sin \ 60^o\\\\F_y = 10.158*10^{-4}[/tex]
The magnitude of the resultant force will be
[tex]\rm F_R = \sqrt{(1.955*10^{-4})^2 + (10.158*10^{-4})}\\\\F_R = 1.034*10^{-3}[/tex]
And the angle will be
[tex]\rm \theta = tan^{-1} \dfrac{F_x}{F_y}\\\\\\\theta = tan^{-1} \dfrac{1.955*10^{-4}}{10.158*10^{-4}}\\\\\\\theta = 10.89^o[/tex]
More about the electrostatic force link is given below.
https://brainly.com/question/9774180