Answer:
3.41334 m
Explanation:
t = Time taken
u = Initial velocity
v = Final velocity
s = Displacement
a = Acceleration
m = Mass
Force
[tex]F=ma\\\Rightarrow a=\frac{F}{m}\\\Rightarrow a=\frac{12}{31}\\\Rightarrow a=0.387\ m/s^2[/tex]
Acceleration of the cart is 0.387 m/s²
[tex]s=ut+\frac{1}{2}at^2\\\Rightarrow s=0\times 4.2+\frac{1}{2}\times 0.387\times 4.2^2\\\Rightarrow s=3.41334\ m[/tex]
The cart will move 3.41334 m in 4.2 seconds