When to use Tsin(theta)=mv^2/r and Tsin(theta)=mg????Please help me out!!!!!!!

[saltrock]

Hi i am quite good on horizontal and vertical circular motion,but i always get confused by this formulae,Tsin(theta)=mv^2/r and T cos(theta)=mg.In what situation i should use sin or coz formula coz i always end up using the wrong formula all the time.i use sin instead of cos and cos instead of sin as i dont know under what circumstance i should use these.Is this related to vertical or horizontal circular motion?

[devious_]

Why don't you draw a sketch of the problem? You could then pick whichever angle you want, and resolve the components of T whichever way you want.

[saltrock]

Thanx for your reply devious