Two long current-carrying wires run parallel to each other and are separated by a distance of 4.00 cm. If the current in one wire is 1.50 A and the current in the other wire is 3.15 A running in the opposite direction, determine the magnitude and direction of the force per unit length the wires exert on each other.

The magnitude of force per unit length the wires exert on each other is 2.36 × 10^-5 N/m.

Since the wires carry currents running in the opposite direction, the force is therefore repulsive.

Explanation: Please see the attachments below

The magnitude of the force F =

The direction of the force is in opposite direction.

Explanation:

The expression for force per unit length between two parallel wires carrying current and can be written as:

permeability constant =

a = distance between the wires = 4.00 cm = 0.04 cm

replacing our values into the above equation; we have:

Hence, If the current flows in the same direction, then , the force is said to be attractive (+ve) . However, if the direction of the current flow is opposite; then the force is said to be repulsive (-ve).

From the question given, the current flows in opposite direction in the wires, thus the force is said to be repulsive.

Thus ; F =

scattering of light by tiny particles in air to produce the colors we see on sky, is dependent on the following factors:

(i) wavelength of light

(ii) size of the scattering particle  

(iii) distance traveled by light through the atmosphere.

according to rayleigh's law of scattering, the amount of scattering is inversely proportional to the fourth power of its wavelength. shorter the wavelength, greater is its scattering. hence violet/blue light is scattered more than red.

sun's light is a composite light ( visible light) with wavelengths in the range 400 nm (violet) to 700 nm (red). as sunlight passes through our atmosphere, the molecules of air scatter light according to their wavelengths. during sunrise and sunset, the sun's position is below the horizon. hence light from the sun travels a greater distance in the atmosphere when compared to its position a noon.

as sunlight enters the earth's atmosphere, blue light is scattered away and at the end of its journey in the sky, only red and orange wavelengths remain in the beam.

hence at sunrise and sunset, the sky appears reddish orange.