A block of carbon is 2.3 cm long and has a square cross-sectional area with sides of 2.1 cm . A potential difference 8.7 V is maintained across its length. What is the resistance of the resistor?
The resistivity of carbon is 6.5 × 10−5 Ω · m .
Answer in units of mΩ
The resistivity of carbon is 6.5 × 10−5 Ω · m .
Answer in units of mΩ
1 Answer
Mar 16, 2018
Good one . See below
Explanation:
Firstly Resistance in milli ohmsof a material is:
where
In your case you have:
This would be the case if there was no current flow.
Applying the voltage causes a 8.7V . means there is current of: