Answer:
hydrogen
Explanation:
pH is a measure of the ion concentration of hydrogen in a solution.
In chemistry, it literally means power of hydrogen ions and it is a measure of the molar concentration of hydrogen ions in a particular solution, thus specifying the acidity, neutrality or basicity of chemical solutions.
Mathematically, the pH of a solution is given by
Hence, a solution with a pH of 7 is neutral.
Also, a solution with a pH below 7 is acidic but basic if it's pH is above 7.
Distance traveled by the ball is given by
here we know that
speed = 20 m/s
times = 0.25 s
now we have
so ball will travel 5 m distance in the given interval of time
Answer:
The correct answer is
Explanation:
The formula for the electron drift speed is given as follows,
where n is the number of of electrons per unit m³, q is the charge on an electron and A is the cross-sectional area of the copper wire and I is the current. We see that we already have A , q and I. The only thing left to calculate is the electron density n that is the number of electrons per unit volume.
Using the information provided in the question we can see that the number of moles of copper atoms in a cm³ of volume of the conductor is . Converting this number to m³ using very elementary unit conversion we get
. If we multiply this number by the Avagardo number which is the number of atoms per mol of any gas , we get the number of atoms per m³ which in this case is equal to the number of electron per m³ because one electron per atom of copper contribute to the current. So we get,
if we convert the area from mm³ to m³ we get .So now that we have n, we plug in all the values of A ,I ,q and n into the main equation to obtain,
which is our final answer.
Answer:
h=2.86m
Explanation:
In order to give a quick response to this exercise we will use the equations of conservation of kinetic and potential energy, the equation is given by,
There is no kinetic energy in the initial state, nor potential energy in the end,
In the final kinetic energy, the energy contributed by the Inertia must be considered, as well,
The inertia of the bodies is given by the equation,
On the other hand the angular velocity is given by
Replacing these values in the equation,
Solving for h,