a) the number of protons is 
more than the electrons
b) 
Explanation:
The net electric charge on the ball is
This electric charge is given by the algebraic sum of the charge of the protons and of the charge of the electrons.
The charge of one proton is:
While the charge of one electron is
So the net charge on the metal ball will be given by
where
is the number of protons
is the number of electrons
So we find:
This means that the number of protons is more than the electrons.
b)
In this case, we want to make the ball neautral, so we have to remove a net charge of Q' such that the new charge is zero:
This implies that the charge that we must remove is
To do that (and to make the ball losing mass at the same time), we have to remove protons, since they have positive charge.
The number of protons that must be removed is:
The mass of one proton is
Therefore, the total mass that must be removed from the ball is
Answer:
Linear expansivity is the fractional increase in length of a specimen of a solid, per unit rise in temperature. If a specimen increases in length from l1 to l2 when its temperature is raised θ°, then the expansivity (α) is given by: l2 = l1(1 + αθ). This relationship assumes that α is independent of temperature. This is not, in general, the case and a more accurate relationship is: l2 = l1(1 + aθ + bθ2 + cθ3…), where a, b, and c are constants.
l2 = l1(1 + αθ).
l2 = l1(1 + aθ + bθ2 + cθ3…),
The answer is B) i am 100% positive
The correct option is C) The angle between the vectors is 120°.
Why?
We can solve the problem and find the correct option using the Law of Cosine.
Let A and B, the given two sides and R the resultant (sum),
Then,
So, using the law of cosines, we have:
Hence, we have that the angle between the vectors is 120°. The correct option is C) The angle between the vectors is 120°
Have a nice day!
