Many of a computer's internal components, such as the random access memory (RAM) and central processing unit (CPU), are very sensitive to electrostatic discharge (ESD). You have probably experienced ESDs yourself, if you have ever shuffled your feet across a carpeted floor and then touched a metal doorknob. You experienced a small shock, as the excess electrons you stripped from the carpet are transferred to the door knob. If the relative humidity in the room is low, the buildup of charge on the surface of your body, which acts like an insulator, can be significant-more than enough to damage a computer's components. To prevent ESDs, people assembling computers will wear antistatic equipment, such as that shown in the photo. The wrist strap is said to be grounded, which gives the static charge a safe conducting path away from the body, thereby protecting the computer components. In walking across a carpeted hallway, a computer technician acquires a charge of -4.79 x 10-⁹ C. Assume he touches one of the contact pins of a RAM module without wearing his antistatic equipment and completely delivers his excess charge through the component. How many electrons enter the RAM module during the discharge?

A student reaches to open a door and gets a small electric shock. She knows that the shock is caused by static electricity, but it seems like in the winter she gets shocked more than in the summer. The student asks her science teacher if there are times of the year when there is more static electricity that builds up than other times of the year. The teacher replies that there is, and it depends on the humidity, or moisture in the air. The more humid the air is, the less static will build up and, therefore, the less you get shocked.   Explain why static electricity does not build up as much when the air is humid. In your response, be sure to include: an explanation of static electricity is formed. an explanation of why the student felt a shock when reaching for the door handle. an explanation of how moisture in the air allows static electricity to dissipate.   Be sure to consider the completeness of your response, supporting details, and accurate use of terms.

Opening of voltage-gated channels is driven by an intramembrane electric field acting on charged voltage-sensor domains. These domains move across the membrane and generate gating (displacement) currents. When these currents are integrated over time, they produce the gating charge generated by a population of channels. What would be the gating charge passing through the external circuit when the flat array of charges moves across the distance a inside the membrane? The hydrophobic thickness of the membrane is d, the dielectric constant ɛ, the density of charges is O and the area of the membrane is A (provide an analytic solution). start end A A a d d