A metal sample of mass M requires a power input P to just remain molten. When the heater is turned off, the metal solidifies in a time T. The heat of fusion of this metal is

L = Pt/M

Explanation:

Power, P= Q/t = mL/t

we know that, (Q=m×l)

Now ⇒l= Pt/M

Thus l= Pt/M

Time to fall 0.25 meter vertically from rest:

D = (1/2) (g) (t²)

0.25m = (1/2) (9.8 m/s²)(t²)

t² = (0.25m) / (4.9 m/s²)

t² = 0.051 sec²

t = 0.226 second

In that amount of time, the mouse sails out

(2.1 m/s) (0.226 sec) = 0.474 meter

horizontally.