An apple of mass 0.5 kg is swing around on a string in a circle in a horizontal plane with a constant speed. The string makes an angle `alpha` with the vertical (See the figure). The radius R of the circle is 3.0 m, it takes 2.0sec for the apple to make one complete rotation, the direction of rotation is indicated in the figure, the apple, at S, is coming towards you. Q is the center of the circle, QP is vertical SQ is in the +x direction, QP in the +y direction, and the +z direction is tangent to the circle at S and points towards you. Assume that `g=10m//sec^(2)` and that the string is massless.

Average acceleration of apple in next 0.5 sec. is

Options

A. `6pihati-6pihatk`
B. `6pihati+6pihatk`
C. `-6pihati+6pihatk`
D. `-6pihati-6pihatk`

Explanation

`a_("avg")=(v_(f)-v_(i))/(t)=(3pihati-3pihatk)/(0.5)({:(V,+,Romega),(V,+,3pi):})`
`=6pihati-6pihatk`