A body is projected at t=0 with a velocity 10 ms−1 at an angle of 60∘ with the horizontal. The radius of curvature of its trajectory at t=1 s is R . Neglecting air resistance and taking acceleration due to gravity g=10 ms−2 , the value of R is:
a. 10.3 m
b. 2.8 m
c. 2.5 m
d. 5.1 m