1. An electric current in a conductor varies with time according to the expressi

Question

1. An electric current in a conductor varies with time according to the expression 1(t) 60sin(80mt), where I is in amperes and t is in seconds. What is the total charge passing a given point in the conductor from t = 0 to t-200s? 2. An engineer needs a resistor with a zero overall temperature coefficient of resistance at 20.0°C. She designs a pair of circular cylinders, one of carbon and one of Nichrome as shown in the figure below. The device must have an overall resistance of R1 + R2-20 independent of temperature and a uniform radius of r = 3.00 mm. Ignore thermal expansion of the cylinders and assume both are always at the same temperature. (a) Can she meet the design goal with this method? (b) If so, state what you can determine about the lengths l1 and l2 of each segment. If not, explain. e.

Explanation / Answer

1)

I(t) = 60*sin(80*pi*t)
We know,
I(t) = dq/dt
dq = I(t).dt
q = Integral 60*sin(80*pi*t)
q = -3/(4*pi) * [cos(80*pi*t) ] from t = 0 to t = 1/200 s
q = 57.3 uC
Total Charge, q = 57.3 C


please post seperate questions in seperate post only.

Related Questions

Navigate

• Browse (All)
• Browse 1
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.