Questions from Modern Physics

Q: Consider the circuit shown in Fig. E25.26. The

Consider the circuit shown in Fig. E25.26. The terminal voltage of the 24.0-V battery is 21.2 V. What are Fig. E25.26: (a). the internal resistance r of the battery and (b) the resistance R of the...

Q: If a “75-W” bulb (see Problem 25

If a “75-W” bulb (see Problem 25.35) is connected across a 220-V potential difference (as is used in Europe), how much power does it dissipate? Ignore the temperature dependence of the bulb’s resistan...

Q: In Europe the standard voltage in homes is 220 V instead of

In Europe the standard voltage in homes is 220 V instead of the 120 V used in the United States. Therefore a “100-W” European bulb would be intended for use with a 220-V potential difference (see Prob...

Q: Consider the circuit of Fig. E25.30.

Consider the circuit of Fig. E25.30. Fig. E25.30: (a). What is the total rate at which electrical energy is dissipated in the 5.0- Ω and 9.0-Ω resistors? (b). What is the...

Q: Electric eels generate electric pulses along their skin that can be used

Electric eels generate electric pulses along their skin that can be used to stun an enemy when they come into contact with it. Tests have shown that these pulses can be up to 500 V and produce current...

Q: A heart defibrillator is used to enable the heart to start beating

A heart defibrillator is used to enable the heart to start beating if it has stopped. This is done by passing a large current of 12 A through the body at 25 V for a very short time, usually about 3.0...

Q: The capacity of a storage battery, such as those used in

The capacity of a storage battery, such as those used in automobile electrical systems, is rated in ampere-hours (A ∙ h). A 50-A ∙ h battery can supply a current of 50 A for 1.0 h, or 25 A for 2.0 h,...

Q: An idealized voltmeter is connected across the terminals of a 15.

An idealized voltmeter is connected across the terminals of a 15.0-V battery, and a 75.0-Ω appliance is also connected across its terminals. If the voltmeter reads 11.9 V, (a). how much power is bein...

Q: A 25.0-Ω bulb is connected across the terminals

A 25.0-Ω bulb is connected across the terminals of a 12.0-V battery having 3.50 Ω of internal resistance. What percentage of the power of the battery is dissipated across the internal resistance and h...

Q: A capacitor made of aluminum foil strips separated by Mylar film was

A capacitor made of aluminum foil strips separated by Mylar film was subjected to excessive voltage, and the resulting dielectric breakdown melted holes in the Mylar. After this, the capacitance was f...