5 because there is 5 electrons. In order for an atom to be neutral it has to have the same amount of positive and negative charges.
Answer:
A )
Explanation:
This change in frequency observation occur due to doppler effect
if the wave source moves,In the time between one wave peak being emitted and the next, the source will have moved so that the shells will no longer be concentric. The wavefronts will get closer together in front of the source as it travels and will be further apart behind it. (see the graph)
when the person standing still in front of the ambulance, he will observe a <em>higher frequency </em>than before as the source travels towards them.

The pitch we hear depends on the frequency of the sound wave.
A high frequency corresponds to a high pitch
as we hear a higher frequency , it makes the <em>pitch higher</em> too
Here we have been given two charged body W and X.
We are asked to determine the nature of charge.
Before coming into conclusion, first we have to understand the electric field lines.
The electric field lines are pictorial representation of imaginary lines which are drawn to denote the electric field in a graphical way.
The electric field line starts from a positive charge and ends at a negative charge.It means for positive charges the electric field lines are outward and for negative charges the filed lines will be inward.
In the given diagram,the filed lines for W is towards W itself.The same is also in case of X.
Hence both the charges must be negative in nature.
Hence the correct answer to the question will be B i.e W negative and X: NEGATIVE.
A. is a neutral substance.
Only neutral substances (like pure water) can have a pH of 7.
Answer:the wave lengths are shorter and faster
Explanation:
Plato