Maximum loss in K . E = Total K . E energy y before collision of two ice blocks
K⋅Emaxloss=
1
2
mv2+
1
2
mv2=mv2
This maximum loss in kinetic energy will be equal to loss in heat to melt two ice block. ⇒mv2=(ms∆θ+mL)2...(i) According to question, L=336×105Jkg−1 S=2100Jkg−1K−1 ∆θ=8∘C From Eq. (i) v=√2(s∆θ+L) =√2(2100×8+336×105) v=840ms−1