4) Although a pleasant hi up to the top of the King Range, at least on sunny day

Question

4) Although a pleasant hi up to the top of the King Range, at least on sunny days, your professor decides to set up an automated radio receiving and record station the signals from the tagged hoary bats that may f over that on migration. automated unit can run 12 volt and draws mAmps. Battery suppliers specify battery capacity by amp hours (Ah). a) Help your professor to determine the minimum Ah battery rating to operate his recording station for a full month assuming that he operates it only 12 hours a day. b) How much work does this battery do to run this station for a month?

Explanation / Answer

a)

A battery of x Ah rating will deliver x amperes of current for one hour before it dies. Alternatively, you can draw 2x amperes of current for 1/2 hour or x/2 ampere current for 2 hours, 3x ampere current for 1/3 hour.

Therefore, if you want to draw 'y' amperes current for 'z' hours, your battery should have a minimum rating of y*z Ah after which it will be exhausted.

In our case, we want to draw 60mA current for 12 hours a day for 30 days.

Hence ,we got y= 0.06A and z= 12* 30 = 360 hours

Hence rating, R = y*z = 0.06*360 = 21.6 Ah

b)

Power is given by, P=V*I

Work done, W = P*time = V*I*t

V=12 volts, I= 0.06A, t= 12*30*3600 =1296000 s

W = 933120 J

c)

the amount of energy required per day = E = V*I*t = 12*0.06* (12*3600) = 31104 J

Since the efficiency of solar panel is only half, it needs to produce twice this much energy

So we need E' = 2*31104 = 62208 J

Now, we have only 4 hours to produce this energy (the sun is therre for 4 h only)

So, the solar panel should produce energy at the rate of = E' / 4hours

P= 62208/(4*3600) = 4.32 Watts

Related Questions

Navigate

• Browse (All)
• Browse 4
• Subjects

---

---

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