posted by .

An automobile battery has an emf of 12.6 V and an internal resistance of 0.0500 . The headlights together present equivalent resistance 5.60 (assumed constant).
(a) What is the potential difference across the headlight bulbs when they are the only load on the battery?
(b) What is the potential difference across the headlight bulbs when the starter motor is operated, taking an additional 35.0 A from the battery?


    a. I=E/(Ri+Rb) = (12.6/(0.05+5.60)=2.23A
    V = I*Rb = 2.23 * 5.60 = 12.49 Volts.

    b. Vb=E-I*Ri=12.6 - (35+2.23)0.05=10.74


    (from chapter 12) At a temperature of 0 °C, the mass and volume of a fluid are 825 kg and 1.17 m3. The coefficient of volume expansion is 1.26 × 10 – 3(C ° ) – 1. (a) What is the density of the fluid at this temperature? (b) What is the density of the fluid when the temperature has risen to 20.0 °C?

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Physics

    Batteries are not perfect. Instead they have an "internal resistance, a catch all phrase which describes the internal chemical workings of the battery which prevents it from providing an unchanging voltage regardless ofnits load. A …
  2. Phyics

    A resistor has a resistance R, and a battery has an internal resistance r. When the resistor is connected across the battery, ten percent less power is dissipated in R than would be dissipated if the battery had no internal resistance. …
  3. physics

    when you connect an unknown resistor across the terminals of a 1.50 V AAA battery having a negligible internal resistance, you measure a current of 18.0 mA flowing through it .A)what is the resistance of the resistor. B) if you now …
  4. Physics

    The battery in the circuit diagram has an EMF of 12V and an unknown internal resistance r. Voltmeter V1 is connected across the battery and voltmeter V2 is connected across the switch S. The resistance of the connecting wires and the …
  5. physics

    Three small lamps are connected to a 24 V battery, as shown in the figure. Assume the battery is ideal (has no internal resistance and given in the figure) and the connecting wires have no resistance. Unlike most real bulbs, …

    Two bulbs are connected in parallel across a source of emf EMF = 10.0V with a negligible internal resistance. One bulb has a resistance of 3.0 Omega , and the other is 2.5 Omega . A resistor R is connected in the circuit in series …
  7. Physics

    A battery has an internal resistance of 0.42. A number of identical light bulbs, each with a resistance of 31.500, are connected in parallel across the battery terminals. The terminal voltage of the battery is observed to be one-half …
  8. physics

    Three resistors are connected to a 20 V battery as shown. The internal resistance of the battery is negligible. (a) What is the current through the 15 resistance?
  9. physics

    A battery of emf and negligible internal resistance is connected to two resistances R1 and R2 in series. What is the potential difference across R2?
  10. physics

    a cell of emf 10v and internal resistance 2ohms is connected in series with an ammeter resistance 0.5ohms and a load of resistance 7ohms. Calculate (A) the potential difference across its terminal (B)the voltage drop

More Similar Questions