Exam 18: Direct-Current Circuits Sources of EMF

In applications where electrical shocks may be more likely,such as around water in kitchens and bathrooms,special outlets called GFI's are used.What does GFI stand for?

What is Kirchhoff's 1st equation for this junction?

Three resistors,each of different value,are used in a circuit with a power source supplying 12 volts.For which of the following resistor combinations is the total power supplied the greatest?

What is the current through the 2-Ω resistor?

In a circuit,a current of 2 A is drawn from a battery.The current then divides and passes through two resistors in parallel.One of the resistors has a value of 66 Ω and the current through it is 0.5 A.What is the value of the other resistor?

What is the maximum number of 50-W light bulbs you can connect in parallel in a 100-V home circuit without tripping the 40-A circuit breaker?

Three 6-Ω resistors are connected in parallel to a 15-V battery.What is the current in any one of the resistors?

Two resistors of values 7 and 17 Ω are connected in parallel.This combination in turn is hooked in series with a 2-Ω resistor and a 20-V battery.What is the current in the 2-Ω resistor?

A hair dryer draws 1,050 W,a curling iron draws 900 W,and an electric light fixture draws 450 W.If all three of these appliances are operating in parallel on a 120-V circuit,what is the total current drawn?

A 10-V-emf battery is connected in series with the following: a 2-μF capacitor,a 2-Ω resistor,an ammeter,and a switch,initially open;a voltmeter is connected in parallel across the capacitor.After the switch has been closed for a relatively long period (several seconds,say),what are the current and capacitor voltage readings,respectively?

Resistors of values 5 Ω,15 Ω,and 22 Ω are connected in parallel across a fresh battery.Which resistor dissipates the greatest power?

Three resistors,with values of 4,6 and 15 Ω,respectively,are connected in parallel.What is the overall resistance of this combination?

Three resistors,each with resistance R₁,are in parallel in a circuit.They are replaced by one equivalent resistor,R.Compare this resistor to the first resistor of the initial circuit.Which of the following statements is true?

A 10-V-emf battery is connected in series with the following: a 2-µF capacitor,a 2-Ω resistor,an ammeter,and a switch,initially open;a voltmeter is connected in parallel across the capacitor.At the instant the switch is closed,what are the current and capacitor voltage readings,respectively?

Resistors of values 5 Ω,17 Ω,and 24 Ω are connected in series across a battery with a small internal resistance.Which resistor dissipates the greatest power?

To find the equivalent resistance of the combination of resistors shown across the 28-V battery by the method of possibly repeated applications of combining resistors in series and /or combining resistors in parallel,the first step would be which of the following?

If R₁ < R₂ < R₃,and if these resistors are connected in parallel in a circuit,which one has the highest current?

When a 19-Ω resistor is connected across a 5-V battery,a current of 489 mA flows.What is the power output delivered by the emf of the battery?

A series RC circuit,which is made from a battery,a switch,a resistor,and a 5-μF capacitor,has a time constant of 8 ms.If an additional 7-μF is added in series to the 5-μF capacitor,what is the resulting time constant?

Using a resistor and two different value capacitors,which of the following combinations in an RC circuit would give the greatest time constant?