A pH scale goes from 0 - 14.
7 is in the middle so it is neutral
The answer is A
Explanation: the conservation of matter means that the mass stays the same
The correct answer is
C. The battery
The battery is a device that provides a potential difference in the circuit, and so an electromotive force (e.m.f.) which pushes the electrons in the circuit from the negative pole towards the positive pole of the battery, so they move through the circuit. Therefore, it provides electrical energy.
Answer:17.44A
Explanation: Current density=I/Area
Area is given by 2.79mm^2=2.79×10^-6m^2
Current=I=current density ×Area=6.25×10^6 ×2.79×10^-6=17.44A
Answer:
(a) 43.2 kC
(b) 0.012V kWh
(c) 0.108V cents
Explanation:
<u>Given:</u>
- i = current flow = 3 A
- t = time interval for which the current flow =

- V = terminal voltage of the battery
- R = rate of energy = 9 cents/kWh
<u>Assume:</u>
- Q = charge transported as a result of charging
- E = energy expended
- C = cost of charging
Part (a):
We know that the charge flow rate is the electric current flow through a wire.

Hence, 43.2 kC of charge is transported as a result of charging.
Part (b):
We know the electrical energy dissipated due to current flow across a voltage drop for a time interval is given by:

Hence, 0.012V kWh is expended in charging the battery.
Part (c):
We know that the energy cost is equal to the product of energy expended and the rate of energy.

Hence, 0.108V cents is the charging cost of the battery.