Answer:

Explanation:
Given:
- Three identical charges q.
- Two charges on x - axis separated by distance a about origin
- One on y-axis
- All three charges are vertices
Find:
- Find an expression for the electric field at points on the y-axis above the uppermost charge.
- Show that the working reduces to point charge when y >> a.
Solution
- Take a variable distance y above the top most charge.
- Then compute the distance from charges on the axis to the variable distance y:

- Then compute the angle that Force makes with the y axis:
cos(Q) = sqrt(3)*a / 2*r
- The net force due to two charges on x-axis, the vertical components from these two charges are same and directed above:
F_1,2 = 2*F_x*cos(Q)
- The total net force would be:
F_net = F_1,2 + kq / y^2
- Hence,

- Now for the limit y >>a:

- Insert limit i.e a/y = 0

Hence the Electric Field is off a point charge of magnitude 3q.
Answer:
2.16×10⁻⁶ N
Explanation:
Applying,
F = kqq'/r² (coulomb's Law)....................... Equation 1
Where F = electrostatic force, k = coulomb's constant, q = charge on the styrofoam, q' = charge on the grain of salt, r = distance between the charges.
From the question,
Given: q = 0.002 mC = 2.0×10⁻⁶ C, q' = 0.03 nC = 3.0×10⁻¹¹ C, r = 0.5 m
Constant: k = 8.99×10⁹ Nm²/C²
Substitute these values into equation 1
F = (2.0×10⁻⁶)(3.0×10⁻¹¹)(8.99×10⁹)/0.5²
F = 2.16×10⁻⁶ N
Answer:
The velocity of the wave is 12.5 m/s
Explanation:
The given parameters are;
he frequency of the tuning fork, f = 250 Hz
The distance between successive crests of the wave formed, λ = 5 cm = 0.05 m
The velocity of a wave, v = f × λ
Where;
f = The frequency of the wave
λ = The wavelength of the wave - The distance between crests =
Substituting the known values gives;
v = 250 Hz × 0.05 m = 12.5 m/s
The velocity of the wave, v = 12.5 m/s.
Answer:
600 J
Explanation:
The formula to find the kinetic energy of an object is
- m = mass in kg
- V = velocity in m/s
- KE is measured in Joules just as all other forms of energy.
Now, let's plug in the variables we're given and simplify.
Thus, the answer is 600 Joules.
I think is a high-pressure system because it is only in one particular area.