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A child’s electronic toy is supplied by three 1.58-V alkaline cells having internal resistances of 0.0200 Ω in series with a 1.53-V carbon-zinc dry cell having a 0.100-Ω internal resistance. The load resistance is 10.0 Ω. (a) Draw a circuit diagram of the toy and its batteries, (b) What current flows? (c) How much power is supplied to the load? (d) What is the internal resistance of the dry cell if it goes bad, resulting in only 0.500 W being supplied to the load?
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- A child's electronic toy is supplied by three 1.58-V alkaline cells having internal resistances of 0.0200 inseries with a 1.53-V carbon-zinc dry cell having a 0.100- internal resistance. The load resistance is 10.0 . (a) Draw a circuit diagram of the toy and itsbatteries, (b) What current flows? (c) How much power is supplied to the load? (d) What is the internal resistance of the dry cell if it goes bad, resulting in only 0.500 W being supplied to the load?arrow_forwardPower P0 = I0 V0 is delivered to a resistor of resistance R0. If the resistance is doubled (Rnew = 2R0) while the voltage is adjusted such that the current is constant, what are the ratios (a) Pnew/P0 and (b) Vnew/V0? If, instead, the resistance is held constant while Pnew = 2P0, what are the ratios (c) Vnew/V0, and (d) Inew/I0?arrow_forwardWhen operating on a 120-V circuit, an electric heater receives 1.30 103 W of power, a toaster receives 1.00 103 W, and an electric oven receives 1.54 103 W. If all three appliances are connected in parallel on a 120-V circuit and turned on, what is the total current drawn from an external source? (a) 24.0 A (b) 32.0 A (c) 40.0 A (d) 48.0 A (e) none of those answersarrow_forward
- Consider the circuit below. The battery has an emf of = 30.00 V and an internal resistance of r = 1,00 . (a) Find the equivalent resistance of the circuit and the current out of the battery. (b) Find the current through each resistor, (c) Find die potential drop across each resistor, (d) Find the power dissipated by each resistor, (e) Find the total power supplied by the batteries.arrow_forwardThe power dissipated in a resistor is given by P = V2/R, which means power decreases if resistance increases. Yet this power is also given by P = I2R, which means power increases if resistance increases. Explain why there is no contradiction here.arrow_forwardA rechargeable battery has an emf of 13.2 V and an internal resistance of 0.850 . It is charged by a 14.7-V power supply for a time interval of 1.80 h. Alter charging, the battery returns to its original state as it delivers a constant current to a load resistor over 7.30 h. Find the efficiency of the battery as an energy storage device. (The efficiency here is defined as the energy delivered to the load during discharge divided by the energy delivered by the 14.7-V power supply during the charging process.)arrow_forward
- Figure P18.19 shows a Wheatstone bridge, a circuit used to precisely measure an unknown resistance R by varying Rvar until the ammeter reads zero current and the bridge is said to be balanced. If the bridge is balanced with Rvar = 9.00 , find (a) the value of the unknown resistance Rand (b) the current in the 1.00 resistor. (Hint: With the bridge balanced, the wire through the ammeter can effectively be removed from the circuit, leaving two pairs of resistors in parallel.) Figure Pl8.19arrow_forwardLightbulb A is marked 25.0 W 120. V, and lightbulb B is marked 100. W 120. V. These labels mean that each lightbulb has its respective power delivered to it when it is connected to a constant 120.-V source. (a) Find the resistance of each lightbulb. (b) During what time interval does 1.00 C pass into lightbulb A? (c) Is this charge different upon its exit versus its entry into the lightbulb? Explain. (d) In what time interval does 1.00 J pass into lightbulb A? (e) By what mechanisms does this energy enter and exit the lightbulb? Explain. (f) Find the cost of running lightbulb A continuously for 30.0 days, assuming the electric company sells its product at 0.110 per kWh.arrow_forwardWhen resistors with different resistances are connected in parallel, which of the following must be the same for each resistor? Choose all correct answers, (a) potential difference (b) current (c) power delivered (d) charge entering each resistor in a given time interval (e) none of those answersarrow_forward
- When resistors with different resistances are connected in series, which of the following must be the same for each resistor? Choose all correct answers. (a) potential difference (b) current (c) power delivered (d) charge entering each resistor in a given time interval (e) none of those answersarrow_forwardPower P0 = I0 V0 is delivered to a resistor of resistance R0. If the resistance is doubled (Rnew = 2R0) while the voltage is adjusted such that the current is constant, what are the ratios (a) Pnew/P0 and (b) Vnew/V0? If, instead, the resistance is held constant while Pnew = 2P0, what are the ratios (c) Vnew/V0, and (d) Inew/I0?arrow_forwardFigure P18.19 shows a Wheatstone bridge, a circuit used to precisely measure an unknown resistance R by varying Rvar until the ammeter reads zero current and the bridge is said to be balanced. If the bridge is balanced with Rvar = 9.00 , find (a) the value of the unknown resistance Rand (b) the current in the 1.00 resistor. (Hint: With the bridge balanced, the wire through the ammeter can effectively be removed from the circuit, leaving two pairs of resistors in parallel.) Figure Pl8.19arrow_forward
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