KVPY SA Exam 2013 Question Paper

Two skaters P and Q are skating towards each other. Skater P throws a ball towards Q every 5 s such that it always leaves her hand with speed $2{\mathrm{ms}}^{-1}$ with respect to the ground. Consider two cases:
(I) P runs with speed $1{\mathrm{ms}}^{-1}$ towards Q while Q remains stationary.
(II) Q runs with speed $1{\mathrm{ms}}^{-1}$ towards P while P remains stationary.
Note that irrespective of speed of P, ball always leaves P’s hand with speed $2{\mathrm{ms}}^{-1}$ with respect to the ground. Ignore gravity. Balls will be received by Q