Answer:
C. The number of positive and negative charges can be the same.
Explanation:
Answer:
here north are not vector option b hope ur help
<span>C.
Sample C would be best, because the percentage of the energy
in an
incident wave that remains in a reflected wave from this material
is the
smallest.
The coefficient of absorption is the percentage of incident sound
that's absorbed. So the highest coefficient of absorption results in
the smallest </span><span>percentage of the energy in an
incident wave that remains.
That's what you want. </span>
<h2>Answer: electrostatic and gravitational force
</h2><h2 />
Mechanical energy remains constant (conserved) if only <u>conservative forces</u> act on the particles.
In this sense, the following forces are conservative:
-Gravitational
-Elastic
-Electrostatics
While the Friction Force and the Magnetic Force are not conservative.
According to this, mechanical energy is conserved in the presence of electrostatic and gravitational forces.
The answere is No pain, no gain