(b) Consider a particular phone that has a battery rated at 4,000 mAh. The battery operates at a potential difference of 3.90 V. How much energy, in units of kilowatt-hours, is stored in a fully charged battery? kWh (c) If electricity costs $0.12 (or 12.0 cents) per kilowatt-hour, what is the value of the total amount of energy stored in this battery? Express your answer in cents (or 0.01 of a dollar). ¢ (d) When the phone is idle (that is, turned on but not making calls or texts, using GPS, or running any power-hungry apps), it will operate continuously for 29.2 hours from a fully charged battery, until the battery runs out. How much average current does the phone draw while idle? Express your answer in milliamperes. mA

Suppose that by mistake you leave ten 50-W light bulbs turned on at your house for 24 hr. Say that the cost of electricity is 6 cents per kW · hr. (i)How many Joules are used by the ten light bulbs over the 24 hours? (ii) calculate the cost for this mistake?

Te-Learning Portal Courses - Reports e-Services ▼ Academic Departments - ETC - CIMS Salim During an experiment to verify Ohm's law, the voltage supplied and the current through a circuit are measured. [Voltage is measured in Volt (V) and current in Ampere (A)]. ww R on Battery The measured value of the current is I = 3.1 ± 0.2 A and that of the voltage is V = 14 0.5 V. The resistance of the circuit (in N) can be calculated using the formula, R = V/I, Calculate the, a) Resistance (in 2) = b) Fractional uncertainty in the resistance = c) Absolute uncertainty (in 2) in the resistance=