BvU said:Not completely clear to me what you mean. For a given voltage, the power dissipated in a heating wire is ##P = I \times V = V^2/R##, so a higher resistance leads to a lower power.
CWatters said:In most cases the voltage is constant (for example the mains voltage is fixed at 110V or 220V). In that case power is proportional to 1/R.
It a few cases the current is constant (for example some types of battery charger). In that case power is proportional to R.
BvU said:See post #2. A lower resistance means a higher current. With the same voltage, the product I x V is then higher.
Power I x V is heat dissipated per unit time
Then with the conservation of energy principle this would be a case of electrical energy transferred to heat energy. The conduction electrons collide with the ionic lattice (resistance) this increases amplitude of thermal lattice vibrations corresponding to temperature increase.BvU said:Not completely clear to me what you mean. For a given voltage, the power dissipated in a heating wire is ##P = I \times V = V^2/R##, so a higher resistance leads to a lower power.
That's correct (if we assume everything else is the same, such as the thermal properties of the heat plates).rede96 said:Right, got it thanks. So for two heater plates given the same voltage the one with the lower resistance will heat to a higher temperature in the same time frame.
The relationship between material resistance and temperature is that as temperature increases, the resistance of a material also increases. This is known as positive temperature coefficient (PTC). Conversely, as temperature decreases, the resistance decreases as well, which is known as negative temperature coefficient (NTC).
Material resistance changes with temperature because as the temperature increases, the atoms in the material vibrate more and collide with electrons, making it more difficult for them to flow. This results in an increase in resistance. Conversely, as temperature decreases, the atoms vibrate less, allowing for easier electron flow and a decrease in resistance.
The type of material plays a significant role in its resistance at different temperatures. Conductors, like metals, have low resistance at room temperature and become more resistant at higher temperatures. Insulators, like rubber, have high resistance at room temperature and become less resistant at higher temperatures. Semiconductors, like silicon, have a more complex relationship with temperature, but generally have an increase in resistance as temperature increases.
Understanding the relationship between material resistance and temperature is crucial for designing and operating electronic devices. It allows engineers to select the appropriate materials for different temperature ranges and ensure the proper functioning of the device. It also helps in predicting and monitoring the performance of electronic components in various environments.
The change in resistance due to temperature can be measured using a thermometer and a multimeter. The thermometer is used to measure the temperature of the material, while the multimeter can measure the resistance of the material. By taking multiple measurements at different temperatures, the relationship between resistance and temperature can be determined.