State Lenz's law and hence describe and explain what happens to a magnet travelling through a metal tube
Lenz's law states that the direction of current due to emf induced by a changing magnetic flux is always such that it opposes the change that induced it.
When a magnet travels through a copper tube this induces an emf and current in the tube, this in turn produces a magnetic field which opposes the direction of motion of the magnet. This means the magnet decelerates through the tube.
MC
Related Physics A Level answers
All answers ▸In terms of particles, explain how resistance arises in metal conductors and why does this resistance increases with temperature.
An atom can become excited by the absorption of photons. Explain why only photons of certain frequencies cause excitation in a particular atom.
Describe and explain the vertical motion of a parachutist which jumps out of an aeroplane at time t=0 and then releases the parachute shortly after reaching terminal velocity at time t=T. (Assume air resistance is not negligible).
Rutherford’s alpha particle scattering experiments gave what evidence about an atom?