A harmonic osillator is represented by `y=0.5cos (1500pi t+0.8)` where 'y' and 't' are in 'm' and 's' respectively. Calculate intial phase or epoch of the particle

Explanation

Given, `y=0.5cos(1500pit+0.8)=0.5sin((pi)/(2)-1500pit-0.8)=0.5sin[-1500pit-(0.8-(pi)/(2))]`
`y=-0.5sin[1500pit+(0.8-(pi)/(2))]`
Now (v) initial phase or cpoch is phase of the particle when `t=0`
i.e. epoch `=0.8-(pi)/(2)=0.8-1.571=-0.771" rad".`