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Electric Current, Ohm's Law and Resistivity
Physics · Chapter 5 · Units 1-2: Electrostatics and Current Electricity
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Your path through this chapter
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Step 1: Not startedFlashcards Beta
30 cards for quick recall of key terms and facts.
Review the cards Step 3: Not startedPractice
65 board-style questions with instant checks: Numerical 18, Multiple choice 17, Short answer 15, Assertion and reason 5.
Practise Step 4: Not startedChapter test Free
Short and long chapter tests in board pattern, with results and analysis.
Step 5: Not started- Chapter test (long) — Electric Current, Ohm’s Law and Resistivity · 40 marks · 100 min
- Chapter test (short) — Electric Current, Ohm’s Law and Resistivity · 20 marks · 50 min
Topics 5
- Free electron theory of conduction; relaxation time; drift velocity; mobility; I = n e A v_d
- Ohm's law; current density J = I/A; J = sigma E; derivation of sigma = n e^2 tau / m and rho = m / (n e^2 tau)
- Resistance, resistivity, conductance and conductivity (R = rho l / A); V-I characteristics of ohmic and non-ohmic conductors
- Temperature dependence of resistance and resistivity of conductors and semiconductors
- Electrical energy and power (P = VI = V^2/R = I^2 R); commercial unit; electricity consumption and billing