In figure "A" of the illustrated circuit, what is the voltage of the battery if the resistance of R1 is 150 ohms, the total resistance is 250 ohms and the current though R2 is 25 milliamps when the switch is closed? See illustration EL-0020.
• In a series circuit, the same current flows through every component (R1 and R2). • Use Ohm’s Law: ( V = I \times R ). • The total resistance is the sum of the resistors in series (R1 + R2 = R_total).
• If the current through R2 is 25 milliamps in this series circuit, what is the current through R1 and the rest of the circuit? • Should you multiply the current by just R1, just R2, or by the total resistance to find the battery voltage? • How do you convert milliamps to amps before using Ohm’s Law so your units are consistent?
• Confirm that the circuit in figure A is a simple series loop with only R1 and R2 as resistances (ignore the ideal fuse and closed switch). • Verify that R_total = 250 ohms is consistent with R1 = 150 ohms plus R2 (what must R2 be?). • Before choosing an answer, convert 25 milliamps to amps and then apply ( V = I \times R_{total} ), checking that your units come out in volts.
No comments yet
Be the first to share your thoughts!