A particle travels with constant speed along a circle of radius `3 m` and completes one revolution in `20 s`. Starting with the lowest point as origin, find (a) the magnitude and direction of the displacement vectors 5 s, 7.5s and 10 s later , (b) the magnitude and direction of the displacement in the 5 s interval from the fifth to the lenth second, (c) average velocity in this interval, (d) the instantaneous velocity at the begining and at the end of the interval.

Answer

(a)4.2 m at `45^@` , 5.5 m at `68^@` and 6 m at `90^@` , (b)4.2 m at `135^@` , (c )`0.85 ms^(-1)` at `135^@` , (d)`0.94 ms^(-1)` at `90^@`, `0.94 ms^(-1)` at `180^@`