If R is the radius of earth, ω is its angular velocjty and gp is the value of g at the poles. The effective value of g at a latitude λ = 600 is    [JIPMER 2018]

The acceleration due to gravity at a latitude λ isg'=g-Rω2cos2λAt the poles,   λ=90°  ∴  g=g=gp              ∵cos90°=0For   λ=60°,  g'=gp-Rω2cos2λor     g'=gp-Rω2cos260°Hence,   g'=gp-Rω2122=gp-14Rω2