prelim-forces-dotpoint help (1 Viewer)

[shkspeare]

"explain the need for a net external force to act in order to change the velocity of an object"

i don't get what to write for this... the only thing on net external force in textbook is newtons first law -.-''
can ne1 help me answer this thank u

 

[jims]

thats because newtons first law IS the only thing on net external force..i think...
anyway, just say something about inertia and that an object wont change its velocity unless acted upon by a non-zero net force.