Explanation:
The electrostatic forces are conservative forces!
The mainly property of the conservative fields is 
In spherical coordinates the field's expression is:

and the curl expression is:

to find the expression for the potential function associated:

A) Wavelength is the distance between two successful crests or troughs in a transverse wave or the distance between two successful compressions or rarefactions in a longitudinal wave. if the wavelength of a wave is long then the wave will diffracts more compared to a wave with a shorter wavelength because the size of the wavelength is proportional to the angle of diffraction. Such that if the gap is larger than the wavelength then the wave passes through the gap and does not spread much on the other side, while when the gap size is equal to the wavelength, maximum diffraction occurs and the waves spread greatly out.
b) Diffraction is a phenomenon that occurs when a wave encounters an obstacles or a slit. It is referred to as the bending of light around corners of an obstacles or aperture into the region of geometrical shadow of the obstacle. It is caused by one wave of light is shifted by the diffracting object which will in turn cause the wave to have interference with itself. (either constructive or destructive)
-- Although it's not explicitly stated in the question,we have to assume that
the surface is frictionless. I guess that's what "smooth" means.
-- The total mass of both blocks is (1.5 + 0.93) = 2.43 kg. Since they're
connected to each other (by the string), 2.43 kg is the mass you're pulling.
-- Your force is 6.4 N.
Acceleration = (force)/(mass) = 6.4/2.43 m/s²<em>
</em> That's about <em>2.634 m/s²</em> <em>
</em>(I'm going to keep the fraction form handy, because the acceleration has to be
used for the next part of the question, so we'll need it as accurate as possible.)
-- Both blocks accelerate at the same rate. So the force on the rear block (m₂) is
Force = (mass) x (acceleration) = (0.93) x (6.4/2.43) = <em>2.45 N</em>.
That's the force that's accelerating the little block, so that must be the tension
in the string.
<span>They both transmit energy </span>
2.4 secs I think
?????????????????????????