At \( t=0 \, \text{s} \), a ball is projected upward with an initial velocity of \( 60 \, \text{m/s} \). At \( t=2 \, \text{s} \), another ball is projected vertically upward with same velocity. The second ball will meet the first ball at \( t = ? \)
(Take \( g=10 \, \text{m/s}^2 \))
