I AM GIVING SOLN ONLY FOR THE LINE IN WHICH THE PARTICLE WOULD BE IN SECOND QUADRNT
LET THETA BE THE ANGLE MADE BY THE LINE PASSING THROUGH (UNDER ROOT 3,1),
THEN TAN THETA=[1/SQRT(3)]
SO WE GET ANGLE IS 30 DEGREE.
ANGLE MADE BY THE NEW POSITION OF THE POINT IS 30+90=120 DEGREES.
ALSO SINCE THE THE LINE JOINING THE NEW POINT AND THE ORIGIN IS OF THE FORM y=mx,
WE GET THAT THE EQUATION OF NEW LINE IS y=(tan 120)x Y=(-SQRT(3))X...................[1]
SOLVING FOR THE EQUATION OF LINE AND CIRCLE SIMULTANEOUSLY WE GET,
x^2+3*x^2=4
x^2=1
x=[-1].......................................................IN SECOND QUADRANT
but slope of the line passing through the new point IS[1/SQRT(3)]
AS @=180-60-90!!!!!!!!!
BUT THERE WILL BE 2 LINES ALONG WHICH PARTICLE MAY MOVE.!!!!!!!!!!
YOU MAY SOLVE TO GET THE ANSWER.