1. The average television is said to be on 6 hours per day. Calculate the yearly cost of electricity, in billions of dollars, required to operate 100 million TVs, assuming their power consumption averages 175 W and the cost of electricity averages 10.5 cents/kW·h.
2. In order to measure the properties of a battery, several resistors are connected to the battery in series and the terminal voltage is measured. In the first case, the resistor has resistance R1 = 2 Ω and the terminal voltage is ΔV1 = 3.4 V. In the second case, the resistor has resistance R2 = 79 Ω and the terminal voltage ΔV2 = 9 V.
c) Express the emf in terms of r, R and ΔV.
d) Find the numerical value of r in Ω.
e) Find the numerical value of ε in V.