I'm trying to help my 7th grader with homework and I don't know this stuff.

How do you figure word problems based on newton's 2nd law.

one problem is: What is the acceleration of a ball if a force of 20N is applied to the 8kg ball?

Newtons second law is Force=mass(acceleration)

F= 20 N
m= 8 kg

Newton (N)= kg.m/s^2

20N=8kg(a)
a=2.5 m/s^2