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What current flows through a 2.54-cm-diameter rod of pure silicon that is 20.0 cm long, when 1.00 x 10ᵌ V is appled to it? (Such a rod may be used to make nuclear-particle detectors, for example.)

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Answer: 1.68 A (Amperes)

Step-by-step explanation:

To calculate the current flowing through the silicon rod, we need to use Ohm's law, which states that the current (I) flowing through a conductor is equal to the voltage (V) applied across it divided by the resistance (R) of the conductor:

I = V/R

The resistance (R) of the silicon rod can be calculated using the formula:

R = ρL/A

where ρ is the resistivity of silicon, L is the length of the rod, and A is the cross-sectional area of the rod.

The resistivity of pure silicon at room temperature is approximately 2.3 x 10^-3 Ω m. The cross-sectional area of the rod can be calculated using the formula for the area of a circle:

A = πr^2

where r is the radius of the rod, which is half of its diameter. Substituting the given values, we get:

r = 2.54/2 = 1.27 cm = 0.0127 m

A = π(0.0127)^2 = 5.083 x 10^-4 m^2

Now we can calculate the resistance of the rod:

R = (2.3 x 10^-3 Ω m)(20.0 cm/100 cm)/5.083 x 10^-4 m^2 = 9.035 Ω

Finally, we can use Ohm's law to calculate the current flowing through the rod:

I = V/R = (1.00 x 10^3 V)/9.035 Ω = 1.68 A

Therefore, the current flowing through the silicon rod is 1.68 Amperes.

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