Answer:

Step-by-step explanation:
You swing one yo-yo around your head in a horizontal circle. The tension acting in the string is equal to the centripetal force. Its formula is given by :

r is the radius of circular path or the length of the string. It remains constant. If the mass of the yo- yo swing is double such that, m' = 2m
New centripetal force is equal to,




So, the new tension in the strings gets doubled.