A silicon ribbon measuring 100 micron thick, 5 mm wide, and 1 m long has 5 volts applied across its long dimension. The resistivity of silicon is 640 ohm-m. How much current will flow through the ribbon? Express your answer in Amps
show you tried and I'll give you an hint ok?
http://en.wikipedia.org/wiki/Electrical_resistivity_and_conductivity
3.906*10^-9 - correct
To find the current that will flow through the silicon ribbon, we can use Ohm's Law, which states that current (I) is equal to voltage (V) divided by resistance (R):
I = V / R
In this case, we are given the voltage (V) applied across the ribbon, which is 5 volts, and the resistivity (ρ) of silicon, which is 640 ohm-m. However, we need to calculate the resistance (R) of the silicon ribbon first.
The resistance (R) of a conductor can be calculated using the formula:
R = (ρ × L) / A
Where:
- ρ is the resistivity of the material
- L is the length of the conductor
- A is the cross-sectional area of the conductor
In this case, the length of the silicon ribbon is 1 m, and the width of the ribbon is 5 mm (which is equivalent to 0.005 m). The thickness of the ribbon is given as 100 microns, which is equivalent to 0.0001 m. To find the cross-sectional area (A), we multiply the width and thickness of the ribbon:
A = width × thickness = 0.005 m × 0.0001 m = 0.0000005 m²
Now, we can calculate the resistance (R) of the silicon ribbon:
R = (640 ohm-m × 1 m) / 0.0000005 m² = 1,280,000 ohms
Now that we have the resistance (R) of the silicon ribbon, we can use Ohm's Law to find the current (I):
I = V / R = 5 volts / 1,280,000 ohms = 0.00000390625 Amps
Therefore, the current flowing through the silicon ribbon is approximately 0.00000390625 Amps.