A real battery with sigma = 1.5 V and internal resistance r = 0.5 ohm is connect
ID: 1525951 • Letter: A
Question
A real battery with sigma = 1.5 V and internal resistance r = 0.5 ohm is connected to a load with R = 2 ohm. (a) hat is the terminal voltage of the battery? (b) Suppose two such identical batteries are connected in series to the same load. What is the terminal voltage of the two batteries? You are designing a flashlight, and there are two options to consider. In the first, the flashlight uses one D-cell (sigma = 1.5 V, E = 20.83 W middot hr) to supply a bulb (R = 2.5 ohm, P = 0.9 W). In the second, the flashlight uses two D-cells to supply a bulb (R = 10 ohm, P = 0.9 W). (a) Determine the current drawn from the battery (s) in each of the cases. (b) Considering the lifetime of the battery (s) in each case, which is the better option?Explanation / Answer
8(a).Emf of real battery E = 1.5 volt
Internal resistance r = 0.5 ohm
Load resistance R = 2 ohm
We know E = i ( R + r )
From this current i = E /(R + r )
= 1.5 /(2+0.5)
= 1.5 / 2.5
= 3/5 = 0.6 A
Terminal voltage of the battery V = iR
= (0.6)(2)
= 1.2 volt
(b).Resultant emf E ' = E + E = 1.5 volt + 1.5 volt = 3 volt
We know E ' = i ' (R + r )
From this current i ' = E ' /( R + r+r )
= 3 /(2+0.5+0.5)
= 3/3
= 1 A
Terminal voltage V ' = i ' R
= (1)(2)
= 2 volt
Related Questions
Hire Me For All Your Tutoring Needs
Integrity-first tutoring: clear explanations, guidance, and feedback.
Drop an Email at
drjack9650@gmail.com
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.