Answer:
The tension is 14 N
Explanation:
For this problem we have to use newton's law, so:
[tex]F=m*a[/tex]
The second string is connected to the mass of 8 kg, but the mass of 8 kg is connected to the mass of 20kg, so we can say that the second string is handling the two masses. so:
[tex]F=28kg*0.5\frac{m}{s^2}=14N[/tex]