How did Newton come up with f ∝ Δp/Δt?

[saidatta123]

How did Newton come up with
f ∝ Δp/Δt ??

 

[bahamagreen]

Galileo's equation for uniform acellerated motion

v=at so multiply both sides by mass m

mv=mat

so
mv=ma(t) and call ma force F

mv=Ft
so
Ft=mv

Divided both sides by t

F=(mv)/t

Didn't Torricelli (Galileo's student) do this before Newton?

Also
F=(mv)/t
so
F=m(v/t) and call v/t acelleration a

F=ma

 

[adjacent]

See this