# Questionable resistance pictures included

• dasblack
In summary, the conversation discusses choosing the appropriate circuit for checking battery voltage drop while supplying a current of 6A. The recommended circuit is Circuit a due to its lower resistance. The headlight has a resistance of 50000 Ohms and the voltmeter is designed to draw as little current as possible. The conversation also highlights the purpose of a voltmeter and its minimal disturbance to the measured voltage.
dasblack

## Homework Statement

You would like to check if the battery voltage drops while it is supplying a current of 6A. You use a voltmeter designed to measure voltages up to 20V and having a resistance of 50,000 Ohms. Which of the two circuits below should be used?
a.) How much current (in A) would flow through the headlight for Circuit a?
b). How much current (in A) would flow through the headlight for Circuit b?

delta(V) = IR

## The Attempt at a Solution

Circuit a should be used because it has the least resistance.

a.) I = 12/50000 = 2.4e-4
b.) I = 12/50000 = 2.4e-4

Before putting the voltmeter into the circuit the current passing in the headlight is 6 amps.
What is the resistance of the headlight?
How does that compare to the resistance of the voltmeter?

The purpose of a voltmeter is to measure a voltage while actually disturbing that voltage as little as possible. Voltmeters are designed to draw as little current as possible.

Now consider which diagram is appropriate.

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The current flowing through the headlight in both circuits is the same because the resistance of the voltmeter is significantly higher than the resistance of the headlight. Therefore, the headlight can be considered a negligible resistance in comparison.

## 1. What are "questionable resistance pictures"?

"Questionable resistance pictures" refer to images or graphics that may depict or suggest resistance to something, but the validity or accuracy of the information presented is uncertain or questionable.

## 2. Why are these pictures included in scientific research or studies?

These pictures may be included in scientific research or studies as a way to illustrate potential findings or hypotheses. However, they should always be critically evaluated and not taken at face value.

## 3. How can one identify if a resistance picture is questionable?

Some signs that a resistance picture may be questionable include lack of credible sources or references, biased or misleading information, and lack of replication or verification from other studies.

## 4. Are questionable resistance pictures always intentionally misleading?

No, sometimes questionable resistance pictures can be unintentional due to human error or misinterpretation. However, it is important for scientists to critically evaluate and verify the information presented in these pictures before using them in their research.

## 5. What should scientists do if they come across questionable resistance pictures in their research?

Scientists should carefully evaluate the reliability and accuracy of these pictures and, if necessary, seek out additional evidence or sources to verify the information. It is important to only use credible and verified information in scientific research.

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