1.

Consider a pair of identical pendulums, which oscillate with equal amplitude independently such that when one pendulum is at its extreme position making an angle of 2^(@) to the right with the vertical, the other pendulum makes an angle of 1^(@) to the left of the vertical. What is the phase difference between the pendulums?

Answer»

Solution :Given situation are SHOWN in given below figures (i) and (ii)

SUPPOSE both the pendulums follows the below functions,
`theta_(1) = theta_(0) sin (omega t+ phi_(1))"""…….."(1)`
`theta_(2) = theta_(0) sin (omega t+phi_(2))"""........."(2)`
where, `theta_(0)=` amplitude
For first pendulum at any time t,
`theta_(1)= +theta_(0)""` (Right side)
From equation (1)
`+ theta_(1)= theta_(0) sin (omega t+phi_(1))`
`THEREFORE +1 = sin(omega t+phi_(1))`
`therefore omega t + phi_(1) = (pi)/(2)""".........."(3)`
Similarly for second pendulum at time t,
`theta_(2) = -(theta_0)/(2)""` (left side)
From equation (2)
`-(theta_0)/(2)= theta_(0) sin (omega t+ phi_(2))`
`therefore -(1)/(2)= sin (omega t+ phi_(2))`
`therefore omega +phi_(2)= -(pi)/(6)" or "(7pi)/(6)"""......."(4)[i.e. = 2pi-(pi)/(6)]`
the difference in phases from equ. (3) and (4)
`(omega + phi_(2))-(omega t-phi_(1))= (7pi)/(6)-(pi)/(2)`
`therefore phi_(2)-phi_(1)= (4PI)/(6)= (2pi)/(3)`
`therefore phi_(2)-phi_(1)= 120^(@)`.


Discussion

No Comment Found