Energy lost = 0.6 × KE
kinetic energy = 1\over 2 × mass × (velocity)2
= 1\over 2 × mass × 52
Energy lost = 0.6 × 1\over 2 × mass × 52
⇒ Energy Available = 0.4 × 1\over 2 × mass × 52
Applying the rule for the conservation of energy we get,
Kinetic energy available = potential energy
⇒ 0.4 × 1\over 2 × mass × 52 = mass × gravity × height
⇒ 1\over 2 × 5 × 5 × 0.4 = 10 × h
⇒ 10h = 1\over 2 × 10
⇒ 10h = 5
⇒ h = 0.5 m
∴ Maximum vertical height reached = 0.5m