tarzan swings from a vine whose length is 10m in a vertical circle under the influence of gravity .when vine make an angle of 20 degree with the vertical then find out length of arc and centripetal force experienced at this instant when tarzan has a speed of 10m/s and weighs 980N

Answer 1

I do not know what length of arc you mean
R = 10
v = 10
Ac = v^2/ r = 100/10 = 10 m/s^2
m = 980/g =980/9.8 =10
so F = m a = 100 Newtons centripetal

surely you want the total force in the vine ?
980 cos 20 + F ????