A ball of mass `1kg` is at rest in position `P` by means two light strings `OP` and `RP`. The string `RP` is now cut and the ball swings to position `Q`. If `theta =45^(@)`. Find the tensions in the strings in position `OP`(when `RP`was not cut ) and `OQ` (when `RP`was cut ). (take `g =10m//s^(2)`).

Explanation

In the first case, ball is in equilibrium (permanent rest). Therefore , net force on the ball in any direction should be zero.
:. `(sum F)` in vertical direction `=0`
or `T_(1) cos theta =mg`
or `T_(1) =(mg)/(cos theta)`

Substituting `m_(1)= 1kg, g=10m//s^(2)` and `theta =45^(@)`
we get, `T_(1) =10sqrt2N`