Question

do is think is centeripital force aplied on humans if yes why if no why

Answer 1

Yes of course centripetal force is applied on the humans!
1) Due to rotation of the earth.
2)Due to revolution of the earth.
Centripetal force is applied on humans ! But the quantity of this force that is applied on humans is negligible. If a person is made to stand on a scale,a force equal to W is there on the person. This force is applied by the scale and this force points to the upward direction. On the other hand, the weight of the person, mg is in the downwards direction. Here , 'm' is the mass of the person and 'g' is the acceleration due to gravity. Now , if the earth would have been at standstill,the upward force , W would have been equal to the downward force, mg. But since the earth revolves, it experiences a centripetal acceleration. But the centripetal acceleration experienced by the person is only 0.3 times the acceleration due to gravity 'g'. Therefore, its only 0.3 % of the upward force that is experienced by the person. And thus, its noted that if the person is not at the poles, his weight is 0.3 % reduced.