The timing device in an automobile's intermittent wiper system is based on an RC time constant and utilizes a 0.520 µF capacitor and a variable resistor. Over what range (in MΩ) must R be made to vary to achieve time constants from 2.50 to 19.0 s?

Range of R is from 4.81MΩ to 36.54 MΩ

Explanation:

Capacitance(C) = 0.520 µF = 0.52 x 10^(-6) F

Time constant = from 2.5 to 19 seconds

In RC circuits, time constant is;

r = RC

Where R is the range (in MΩ)

And r is time constant

Thus,

R = r/c

So minimum range will be at 2.5seconds.

Thus; Rmin = 2.5/(0.52 x 10^(-6)) = 4.81 x 10^(6) Ω = 4.81MΩ

Rmax = 19/(0.52 x 10^(-6)) = 36.54 x 10^(6) Ω = 36.54 MΩ

nec chapter 5 contains

c. information on special occupancy areas

nec chapter 6 covers

a. special equipment

which of the following rules contain the words shall or shall not and must be adhered to?

b. mandatory rules

which of the following rules identify actions that are allowed but not required and typically cover options or alternative methods?

c. optional rules

which of the following serves as the introduction to the nec and provides an overview of the book?

a. nec article 90

organizations that test products for safety are

c. nrtls

the nec is published by the

a national fire protection association

the nec is divided into

b. 9 chapters

the nec provides informative annexes for

c. informational materials and examples

two terms from nec article 100 that trainees should become familiar with are

b. labeled and listed

explanation:

dopamine..

"it was found that some people who were taking the drug l-dopa to raise their levels of dopamine were developing schizophrenic-like symptoms supporting research a strength of the dopamine hypothesis is that there are many studies which have shown support for the neurochemical explanation."