Answer:
3.135 kN/C
Explanation:
The electric field on the axis of a charged ring with radius R and distance z from the axis is E = qz/{4πε₀[√(z² + R²)]³}
Given that R = 58 cm = 0.58 m, z = 116 cm = 1.16m, q = total charge on ring = λl where λ = charge density on ring = 180 nC/m = 180 × 10⁻⁹ C/m and l = length of ring = 2πR. So q = λl = λ2πR = 180 × 10⁻⁹ C/m × 2π(0.58 m) = 208.8π × 10⁻⁹ C and ε₀ = permittivity of free space = 8.854 × 10⁻¹² F/m
So, E = qz/{4πε₀[√(z² + R²)]³}
E = 208.8π × 10⁻⁹ C × 1.16 m/{4π8.854 × 10⁻¹² F/m[√((1.16 m)² + (0.58 m)²)]³}
E = 242.208 × 10⁻⁹ Cm/{35.416 × 10⁻¹² F/m[√(1.3456 m² + 0.3364 m²)]³}
E = 242.208 × 10⁻⁹ Cm/35.416 × 10⁻¹² F/m[√(1.682 m²)]³}
E = 6.839 × 10³ Cm²/[1.297 m]³F
E = 6.839 × 10³ Cm²/2.182 m³F
E = 3.135 × 10³ V/m
E = 3.135 × 10³ N/C
E = 3.135 kN/C
Answer:
The equation of motion is 

Explanation:
Lets calculate
The weight attached to the spring is 24 pounds
Acceleration due to gravity is 
Assume x , is spring stretched length is ,4 inches
Converting the length inches into feet 
The weight (W=mg) is balanced by restoring force ks at equilibrium position
mg=kx
⇒ 
The spring constant , 
= 72
If the mass is displaced from its equilibrium position by an amount x, then the differential equation is



Auxiliary equation is, 

=
Thus , the solution is 

The mass is released from the rest x'(0) = 0
=0


Therefore ,

Since , the mass is released from the rest from 4 inches
inches
feet
feet
Therefore , the equation of motion is 
You would have to pick the word c because that is the answer