A student performed an experiment to investigate how the resistance of a metallic conductor changes with temperature - Leaving Cert Physics - Question 4 - 2020

The instrument used to measure temperature is a thermometer or a temperature probe designed for measuring temperatures in experiments.

The student changed the temperature of the metallic conductor by placing it in a liquid heat source. This method allows for controlled heating and precise measurements of temperature changes.

To plot the graph:

1. Label the x-axis as Temperature (°C) and the y-axis as Resistance (Ω).
2. Plot the following points:
   • (10, 4.8)
   • (20, 5.4)
   • (30, 6.0)
   • (40, 6.6)
   • (50, 7.2)
   • (60, 7.8)
   • (70, 8.4)
3. Include a line of best fit to connect the points.
4. Ensure all points are correctly positioned, and observe for any error margin in plotting. The graph should show a positive linear relationship.

The relationship between resistance and temperature is generally linear in metallic conductors. As the temperature increases, the resistance of the metallic conductor also increases. This relationship occurs due to increased atomic vibrations at higher temperatures, which impedes the flow of electrons, thereby increasing resistance. Mathematically, this can be expressed as a linear equation:

$R = mT + c$

where R is resistance, T is temperature, m is the slope indicating how resistance changes with temperature, and c is the y-intercept.

One safety precaution the student should have taken is to be careful of hot surfaces and to use protective equipment, such as heat-resistant gloves, to avoid burns while handling the heated metallic conductor.