Derive I = nAVe
Over 1 second, electrons with drift velocity V travel through a wire of cross sectional area A. Distance Vt (t = 1) multiplied by area A gives a volume AV. This volume multiplied by the electron density of the material n, gives the number of electrons in volume V, nAV. The charge in the volume of material is found by multiplying the number of electrons by the elementary charge e, nAVe. This is the amount of charge passing through the wire every second, or current I. Therefore, I = nAVe
DD
Related Physics A Level answers
All answers ▸Derive an expression to show that for satellites in a circular orbit T² ∝ r ³ where T is the period of orbit and r is the radius of the orbit.
A guitar string 0.65m long vibrates with a first harmonic frequency of 280Hz. Mary measures 1m of the string and discovers that it weighs 8.0x10^-4 kg. What is the tension in the guitar string?
What is meant by the doppler effect?
What is the root mean square voltage of an alternating current?