which property of light does compass uses
Answers
Answer:
A compass in the earth's field can be thought of as a damped oscillator: on the one hand there's the torque on the needle that is proportional to the displacement from magnetic North, on the other there's the inertia of the needle; and finally, there are damping terms (a good compass is critically damped - meaning that the damping is such that it will go to the right position in the shortest time). We can write the equation of motion as
Iθ¨+μθ˙+kθ=0
In this expression, μ is the damping term (proportional to the angular velocity) and k is the factor that describes how much torque the needle experiences with displacement.
This is a general equation for a Simple Harmonic Oscillator (SHO), and we typically recognize three regimes: lightly damped, heavily damped, and critically damped.