Two blocks of masses m and M are suspended as shown above by strings of negligible mass. If a person holding the upper string lowers the blocks so that they have a constant downward acceleration a, the tension in the string at point P is

Answer 1

This is an example of why some questions go unanswered.
There are no diagrams or graphics or images on this web site.
Unfortunately, this is not clearly explained when students post their questions and attempt to include figures.

Answer 2

If anyone still cares, the image is a string above box m with another string connecting rectangle M underneath with a P in the middle. I wish I could upload a graph but I guess this site doesn't want me to.