Answer: electric field
Explanation: when a charge is placed in space, it alters the space around it by creating an electric field.
This electric field has the ability to exert a force (f) on any test charge(q) placed within this vicinity.
This is the reason why a charge can either attract or repel another charge.
I assume that the ball is stationary (v=0) at point B, so its total energy is just potential energy, and it is equal to 7.35 J.
At point A, all this energy has converted into kinetic energy, which is:

And since K=7.35 J, we can find the velocity, v:
Answer: -33.3 * 10^9 C/m^2( nC/m^2)
Explanation: In order to solve this problem we have to use the gaussian law, the we have:
Eoutside =0 so teh Q inside==
the Q inside= 4.6 nC/m*L + σ *2*π*b*L where L is the large of the Gaussian surface and b the radius of the shell.
Then we simplify and get
σ= -4.6/(2*π*b)= -33.3 nC/m^2
All ions are atoms with a charge
Answer: 5.5
Explanation:
Let's start by explaining that hardness is a property that materials have related to the opposition or resistance they offer to alterations such as penetration, abrasion, scratching, cutting, and permanent deformations, among others.
In this context, several hardness scales have been developed to catalog the materials (specifically minerals), being the Mohs scale the best known. This scale, proposed by the German geologist Friedrich Mohs in 1825, consists of a ratio of ten minerals numbered in increasing order by hardness, from least to greatest.
This is how the scale starts at 1 with the talc (considered the softest material) and ends at 10 with the diamond as the hardest.
Now, if we are told that the glass is in the middle of the hardness scale that goes from 1 to 10, logically its value will be 5 (volcanic glass). However, according to the scale, the glass is at 5.5.