Question

A cylindrical sample of solid germanium has length 55.0 mm and diameter 5.0 mm. In a test circuit, 0.150 A of current flowed through this sample when the voltage applied between its ends was 17.5 V. What is the electrical conductivity of this sample?

Answer 1

To calculate the current flow through the silicon rod, we can use Ohm's Law. First, calculate the resistance of the rod using the formula R = ρ * (L/A). Then, use Ohm's Law to find the current by rearranging the formula to I = V/R.

Step-by-step explanation:

To calculate the current flowing through the rod, we can use Ohm's Law, which states that the current (I) is equal to the voltage (V) divided by the resistance (R). First, let's calculate the resistance of the rod using the formula R = ρ * (L/A), where ρ is the resistivity of the material, L is the length of the rod, and A is the cross-sectional area of the rod.

For silicon, the resistivity is approximately 640 Ω * cm. The length of the rod is 20.0 cm, and the diameter is 2.54 cm, which gives a radius of 1.27 cm. The cross-sectional area (A) of the rod can be calculated using the formula A = π * r^2.

Once we have the resistance, we can use Ohm's Law to calculate the current by rearranging the formula to I = V/R. Substituting the given values, we get I = 1.00 × 10^3 V / R.