Answer:
a) 0 m/s
b) 4 m/s
Explanation:
The average velocity would end up being 0 because it is displacement over time and the displacement here is 0. However, speed is total distance over time which here is 400/100 so it is 4.
Answer:
a) pressure means force acted on a body per unit area
Answer:
a) 0.15 μC b) 9.4*10¹¹ electrons.
Explanation:
As the total charge must be conserved, the total charge on the spheres, after being brought to contact each other, and then separated, must be equal to the total charge present in the spheres prior to be put in contact:
Q = +8.2μC +9.0 μC +(-7.8 μC) + (-8.8 μC) = +0.6 μC
As the spheres are assumed perfect conductors, as they are identical, once in contact each other, the excess charge spreads evenly on each sphere, so the final charge, on each of them, is just the fourth part of the total charge:
Qs = Qt/4 = 0.6 μC / 4 = 0.15 μC.
b) As the charge has a positive sign, this means that each sphere has a defect of electrons.
In order to know how many electrons are absent in each sphere, we can divide the total charge by the charge of one electron, which is the elementary charge e, as follows:
![N =\frac{0.15e-6C}{1.6e-19C} = 9.4e11 electrons](https://tex.z-dn.net/?f=N%20%3D%5Cfrac%7B0.15e-6C%7D%7B1.6e-19C%7D%20%20%3D%209.4e11%20%20electrons)