Answer
The resistance of a material depends on its length, cross-sectional area, and resistivity. This is expressed by the following equation:
resistance = [(resistivity x length) / cross-sectional area]
So, resistance is directly-proportional to the resistivity and length of the material, and inversely-proportional to its cross-sectional area. So a high resistance can be obtained by increasing the length of the material or by decreasing its cross-sectional area, or by choosing a material with a high resistivity.
It's also worth pointing out that resistivity is affected by temperature. For pure metals, the higher the temperature, the higher the resistivity, so the higher the resisistance. For example, a hot (i.e. an operating) tungsten lamp will have a much higher resistance than a cold tungsten lamp.
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