J.R. S. answered 01/31/24
Ph.D. University Professor with 10+ years Tutoring Experience
You are converting N/cm to N/mm, so we need to know the conversion of cm to mm (centimeters to millimeters). There are 100 cm in 1 meter. There are 1000 mm in 1 meter. Thus, there are 10 mm in 1 cm.
Now, plug this into the equation and notice how the units of cm cancel, leaving units of mm.
0.070 N / cm x 1 cm / 10 mm = 0.0070 N / mm.
So, the ? in the equation is 1 cm / 10 mm