what is the mass of a rock if a number 12 N unbalanced force acting on it causes the rock to accelerate at 4 m/s^2

a. 0.33 kg

b. 3 kg

c. 48 kg

Respuesta :

We can use Newton's second law to find out.  This says F=ma, where m is the mass we seek:
[tex]F=ma \\ \\ 12N=m(4 \frac{m}{s^2}) \\ \frac{12N}{4 \frac{m}{s^2}} =3kg[/tex]

So we see the mass is 3kg