# Basic Electricity (what i should know but don't)

• chaz699
In summary, the conversation discusses how to calculate the maximum resistance of a filament lamp using a graph of V against I. The speaker suggests drawing a tangent line on the steepest point of the graph and using it to form a right angled triangle to calculate the maximum resistance accurately.
chaz699
i have been given this question

Figure 1 shows a graph of V against I for a filament lamp. Calculate the maximum resistance of the lamp over the range shown by the graph,

now i have a somewhat vague attempt and its to measure the tangent of the line (i can't upload the graph sorry)

how do i take a tangent of a curved line accurately and then calculate the maximum resistance

You just need to take a little time and care drawing your tangent.The graph should be steepest at the origin where the resistance is highest..Draw your tangent as long as you can ,construct a right angled triangle where the tangent becomes the hypotenuse and divide the change of voltage by the change of current(tan theta)

As a scientist, it is important to have a strong understanding of basic electricity concepts, including resistance. In order to accurately calculate the maximum resistance of a filament lamp shown in Figure 1, it is important to first understand the relationship between voltage (V) and current (I) in a circuit.

The slope of the V-I graph represents the resistance of the circuit, with the steeper the slope, the higher the resistance. Therefore, to calculate the maximum resistance, you would need to find the steepest slope on the graph.

One way to do this is by using a ruler and drawing a tangent line at different points along the curve of the graph. The tangent line should be drawn so that it just touches the curve at that point. Then, you can measure the slope of each tangent line using the ruler and calculate the resistance using the formula R = V/I.

Another method is to use a graphing calculator or software that allows you to plot the curve and find the equation of the line of best fit. The slope of this line would also give you the maximum resistance.

It is important to note that the maximum resistance may not necessarily be at the highest point on the graph, as the curve may have a different shape or slope at different points. Therefore, it is important to carefully analyze the graph and choose the most appropriate method to accurately calculate the maximum resistance.

I hope this helps to clarify the process for calculating the maximum resistance of a filament lamp. Remember to always approach scientific questions with a critical and analytical mindset, and to seek out additional resources and guidance when needed.

## 1. What is the difference between AC and DC electricity?

The main difference between AC (alternating current) and DC (direct current) electricity is the direction in which the current flows. In AC electricity, the direction of the current periodically switches back and forth, while in DC electricity, the current flows in only one direction. AC electricity is used for power distribution, while DC electricity is commonly used in batteries and electronic devices.

## 2. What is voltage and how is it measured?

Voltage is the force or pressure that pushes electric charges through a circuit. It is measured in volts (V) and can be measured using a voltmeter. Voltage is often compared to water pressure in a pipe, where a higher voltage means more force pushing the charges through the circuit.

## 3. What is resistance and how does it affect electricity?

Resistance is the measure of how difficult it is for electric current to flow through a material. It is measured in ohms (Ω) and is affected by factors such as the type of material, its length, and its cross-sectional area. The higher the resistance, the more difficult it is for current to flow, resulting in a decrease in the flow of electricity.

## 4. How does electricity travel through a circuit?

Electricity travels through a circuit in a closed loop, from a power source (such as a battery or generator) to a load (such as a light bulb or motor) and back to the power source. The flow of electricity is driven by the difference in voltage between the positive and negative terminals of the power source.

## 5. What safety precautions should be taken when working with electricity?

When working with electricity, it is important to always turn off the power source and wear protective gear, such as rubber gloves, to prevent electric shock. Make sure to never touch exposed wires and always use insulated tools. It is also important to not overload circuits and to have a fire extinguisher nearby in case of emergencies.

• Introductory Physics Homework Help
Replies
19
Views
2K
• Introductory Physics Homework Help
Replies
9
Views
232
• Introductory Physics Homework Help
Replies
1
Views
1K
• Introductory Physics Homework Help
Replies
8
Views
2K
• Introductory Physics Homework Help
Replies
12
Views
5K
• Introductory Physics Homework Help
Replies
20
Views
3K
• Introductory Physics Homework Help
Replies
8
Views
4K
• Introductory Physics Homework Help
Replies
7
Views
5K
• Introductory Physics Homework Help
Replies
9
Views
1K
• Introductory Physics Homework Help
Replies
6
Views
1K