Answer:
a) [tex]a_{ball} = 6000\,\frac{m}{s^{2}}[/tex], b) [tex]F = 840\,N[/tex]
Explanation:
a) The physical system for the ball is modelled after the Impulse Theorem. The Impulse to accelerate the ball is:
[tex]Imp =m_{ball}\cdot v_{f}[/tex]
[tex]Imp = (0.14\,kg)\cdot (12\,\frac{m}{s})\\Imp = 1.68\,N\cdot s[/tex]
The acceleration of the ball is derived as follows:
[tex]a_{ball}=\frac{Imp}{m_{ball}\cdot\Delta t}[/tex]
[tex]a_{ball} = \frac{1.68\,N\cdot s}{(0.14\,kg)\cdot(2\times 10^{-3}\,s)}[/tex]
[tex]a_{ball} = 6000\,\frac{m}{s^{2}}[/tex]
b) The net forced is obtained by the use of the concept of force for a system with a constant mass:
[tex]F = (0.14\,kg)\cdot(6000\,\frac{m}{s^{2}} )[/tex]
[tex]F = 840\,N[/tex]