Concept explainers
BIO Electric discharge by eels In several aquatic animals such as the South American electric eel electric organs produce 600-V potential difference pulses to ward off predators as well as to stun prey Figure 18.29 illustrates the key component that produces this electric shock—an electrolyte. The interior of an inactive electrolyte (Figure 18.29a) has an excess of negatively charged ions. The exterior has an excess of positively charged sodium ions
The eel's long trunk and tail contain many electrolytes placed one after the other in columns (Figures 18.29b and c). Each electrolyte contains several types of ion channels, which when activated by a nerve impulse allow sodium ions to pass through channels on the loft flat side of each electrolyte from outside the cell to the inside. This causes the electric potential across that cell membrane to change from
Suppose you have a 1.0-F capacitor (very large capacitance) with a 0.10-V potential difference across the capacitor. What is the magnitude of the electric charge on each plate of the capacitor?
a. 0.05 C
b. 0.10 C
c. 0.20 C
d. 1.0 C
e. 10 C
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