Answer:
It is said that the negative charge moves because the electrons in the atoms of any object are taken or given to the atoms of another object.
Explanation:
The atom is made up of protons, electrons and neutrons. The number of protons is exactly the same to the number of electrons for a certain element. For example, hydrogen: it has a proton, and therefore, an electron.
The electron has a negative charge. The proton has a positive charge. And the neutron has no charge, so it is neutral. While the atom has the same number of protons and electrons, it will not be electrically charged.
An example of how a charge exchange occurs between two objects is through the case of rubbing. This makes the atoms of the two objects close enough that there is an electron transfer, causing any of the objects to gain or lose electrons as a consequence of each other interaction. In the case of transferring electrons, the atom will have a greater number of protons, so it will be positively charged. When the atom receive electrons, it will have a greater number of electrons, so it will be negatively charged.
Therefore, since it is the electrons that move from one atom to another, then it is the negative charge that moves (<em>characterized by the electrons</em>) and not the positive charge (<em>characterized by the protons</em>).
Answer:
amount of energy = 4730.4 kWh/yr
amount of money = 520.34 per year
payback period = 0.188 year
Explanation:
given data
light fixtures = 6
lamp = 4
power = 60 W
average use = 3 h a day
price of electricity = $0.11/kWh
to find out
the amount of energy and money that will be saved and simple payback period if the purchase price of the sensor is $32 and it takes 1 h to install it at a cost of $66
solution
we find energy saving by difference in time the light were
ΔE = no of fixture × number of lamp × power of each lamp × Δt
ΔE is amount of energy save and Δt is time difference
so
ΔE = 6 × 4 × 365 ( 12 - 9 )
ΔE = 4730.4 kWh/yr
and
money saving find out by energy saving and unit cost that i s
ΔM = ΔE × Munit
ΔM = 4730.4 × 0.11
ΔM = 520.34 per year
and
payback period is calculate as
payback period = 
payback period = 
payback period = 0.188 year
Answer:
Earth's tilted axis causes the seasons. Throughout the year, different parts of Earth receive the Sun's most direct rays. So, when the North Pole tilts toward the Sun, it's summer in the Northern Hemisphere. And when the South Pole tilts toward the Sun, it's winter in the Northern Hemisphere.
As we know that electric field at any point caused due to a point charge given by, kQ/r^2
Where, k is dielectric constant of medium, Q is the point charge and r is the distance between the point charge and point where electric field is to be measured.
Let us assume a charge of q is placed at x=+20cm to make electric field at
x=+10cm zero.
Total electric field at x=+10cm can be shown by equation,
(k X 2.20 X 10^-12)/(10-0)^2 + (k X -4.80 X 10^-12)/(10-(-11))^2 + (k X
q)/(10-20)^2 = 0
=> 2.20 X 10^-14 - 1.09 X 10^-14 + q X 10^-2 = 0
=> q = 1.09 X 10^-12 - 2.20 X 10^-12
=> q = -1.1 X 10^-12 Coulombs or -1.1 pC