- #1

isorounded

**1. The problem statement**

I did a laboratory work in which I had to find power and internal resistance. I used an ordinary battery so it's closed circuit. I did all tasks except writing a hypothesis and conclusion I can't really think of it. I don't know what to write since I just measure using voltmeter and ammeter and then calculate Electric power and internal resistance. Can someone suggest anything pls?

## Homework Equations

E - [/B]emf, electromotive force

**r**- internal resistance

**ap**- calculated

**U**- voltage

**I**- current

## The Attempt at a Solution

Well from ammeter and voltmeter I got that

**Uap= 2V**,

**Iap= 1,5**A and

**Eap= 4V**. Then I calculated rap (

**rap=1,33**ohms). I found delta u(

**△u=+-0,25)**, delta I (

**△I=+-0,03)**and I know that electromotive force error is almost same as voltage error because power supply's resistance is usually low so

**R≥r**and

**△E =**. I found Er what led me to finding

**△u = +-0.25 V****△r.**. Now I am bit confused we the results I got

**△r = rap+Er = 1,33 * 0.27= 0.3591 ohms****E = 4 +- 0.25 V**and

**r = 1.33 +- 0,3591**ohms, please let me know if I did it wrong. Now the main thing I struggle with is writing hypothesis and conclusion. I was thinking to relate given formulas with ohm's law and formula but not sure if it's good. So can someone help me to write hypothesis and conclusion or atleast give me some ideas. Thank you.