A battery is rated at 12 V and 160 A-h. How much energy does the battery store? What is the cost of this energy at $0. 15/kWh?
1 answer:
Answer:
The cost of energy is 0.29$.
Explanation:
Given that,
Voltage V= 12 V
Charge Q= 160 A-h
We need to calculate the energy
Using formula of energy
Where, E = energy
I= current
V = Potential
t = time
Put the value into the formula
The cost of this energy at 0.15/kwh
Here, Energy = power x time
In units,
But , Energy in 1 hour is:
So, The cost of this energy is
Hence, The cost of energy is 0.29$.
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b)
When the rod touches sphere A, some electrons are transferred from the rod to the sphere (this method of charging is called charging by conduction).
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c)
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Therefore, the net charge of the rod + wool system will now be positive.
d)
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Since sphere A is charged negatively, when it is brought close to sphere B, the electrons in sphere B will be attracted on the opposite side relative to sphere A, while the positive charges will migrate close to sphere A. Therefore, the two spheres will attract each other, since opposite charges attract each other.
e)
When the plastic rod (which is negatively charged) touches sphere B, some electrons are transferred to sphere B (charging by induction). As a result, charge B will also be negatively charged now, as it has an excess of electrons.
At the same time, sphere A is also negatively charged. Therefore, as like charges repel each other, this means that the two spheres will now repel each other.
f)
The net charge of the rod and the two spheres is negative.
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Since the net charge on the rod before the process was negative, then the net charge of the system consisting of the rod + 2 spheres must be negative as well.
g)
When a glass rod is rubbed with silk, charging by friction occurs, similar to part a). However in this case, the glass rod gives off electrons to the silk: therefore, the glass rod remains positively charged.
Later, the glass rod touches sphere B: as a result, positive charge is transferred from the rod to sphere B, so sphere B will remain positively charged.
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h)
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where
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