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A heating element made of tungsten has a resistance of 40.0 Ω at 600°C. Determine its resistance when the temperature is 10°C.
A rod has a resistance R. A craftsman fabricates the rod to create a new rod that has 4 times the length of the original rod. Assuming the new rod has the same density and resistivity, and all material is conserved, determine the rod's resistance in terms of R.
You are working on a circuit that requires an ammeter with a full-scale reading of 75.0 mA. However, the only ammeter available in the storeroom has a range from 0 μA to a full-scale reading of 300.0 μA. The resistance of the ammeter is measured to be 60.0 Ω. To achieve the desired 75.0 mA reading capacity, you consider adding a resistor in parallel to the ammeter. Calculate the effective resistance of the modified ammeter (which is a combination of the ammeter and the parallel resistor).

Construct a circuit diagram (using proper symbols) for the circuit illustrated in the provided figure.

A cerebrospinal fluid with a conductivity of 1.7 Ω-1 m-1 flows through a cylindrical pipe representing a segment of the neuron. The pipe has a radius of 0.5 mm. Calculate the resistance of a 5.0 cm long column of cerebrospinal fluid.
The 3.8 V battery of a smartphone experiences an increase in its internal resistance due to exposure to extreme temperatures. Consequently, the battery's efficiency decreases, resulting in a shorter life. The cell phone can be connected to an external power source to charge its internal battery. Assume that the smartphone battery and the external power source are connected to a 0.75 Ω resistor, as illustrated in the figure below. Determine the current that passes through the 0.75 Ω resistor if the switch is closed.

Composite materials with varying compositions exhibit resistance variations along their length, allowing for the creation of customizable resistance profiles. Let's consider a wire composed of a composite material aligned in the y-direction with a radius of 1.5 mm and a resistivity expressed as ρ(y) = (2.7 × 10 -4 Ω•m ) e[-(3.5 /m)• y], where y represents the distance from the lower end of the wire. Calculate the resistance of a 30.0 cm long wire.