Answer:
[tex]4\cdot 10^4 m/s^2[/tex]
Explanation:
The acceleration of an object is given by Newton's second law:
[tex]a=\frac{F}{m}[/tex]
where
F is the net force applied on the object
m is the mass of the object
For the book in the problem, we have:
[tex]m=0.5 g =5\cdot 10^{-4} kg[/tex] is the mass
[tex]F=20 N[/tex] is the force applied
Substituting into the formula, we find the acceleration:
[tex]a=\frac{20 N}{5\cdot 10^{-4} kg}=4\cdot 10^4 m/s^2[/tex]
