The size of a filament has a direct relationship with its resistance - as the size increases, the resistance also increases. This is because a larger filament has a larger cross-sectional area, which allows for more electrons to flow through it, resulting in a lower resistance.
The material of the filament also plays a significant role in its resistance. Materials with higher resistivity, such as tungsten, will have a higher resistance compared to materials with lower resistivity, like copper. Therefore, the material of the filament can impact its resistance even if the size remains constant.
Yes, the resistance of a filament can change over time due to factors such as temperature, stress, and exposure to certain gases. For example, as a filament is heated, its resistance will increase due to the increase in thermal energy causing an increase in electron collisions.
The length of a filament also has a direct relationship with its resistance - as the length increases, the resistance also increases. This is because a longer filament will have a higher resistance due to the increase in distance electrons must travel to flow through it.
The resistance of a filament can be calculated using Ohm's Law, which states that resistance is equal to voltage divided by current. You can measure the voltage and current of the filament using a multimeter and then use the equation R=V/I to calculate the resistance. Alternatively, you can also use the formula R=pL/A, where p is the resistivity of the material, L is the length of the filament, and A is the cross-sectional area.