Answer:
The magnitude of the electric field at distance r from the point charge q is 
Explanation:
Suppose, Find E(r), the magnitude of the electric field at distance r from the point charge q.
We know that,
The electric field is proportional to the point charge and inversely proportional to the square of the distance from the charge point .
In mathematically,

Where, q = charge point
R = distance from charge point
Hence, The magnitude of the electric field at distance r from the point charge q is 
Answer:
3 x 10^-4 N/m
Attractive
Explanation:
r = 0.1 m, i1 = 10 A, i2 = 15 A
The force per unit length between two parallel wires is given by


F = 3 x 10^-4 N/m
Thus, the force per unit length between two wires is 3 x 10^-4 N/m, the force is attractive in nature because the direction of flow of current in both the wires is same.
Answer:
Useable energy, electricity
Brushes, battery terminals, commutator, armature, magnets
Explanation:
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