Question

Water is falling on a surface, wetting a circular area that is expanding at a rate of 6mm^2/s. How fast is the radius of the wetted area expanding when the radius is 109nm. (Round your answer to four decimal places.)

Answer 1

Answer:

0.0622ns

Step-by-step explanation:

Rate, R = 6mm²/s or 6 X 10∧-8m²/s

Radius, r = 109 X 10∧-9m

Area of circular object = πr² = 22/7 X (109 X 10∧-9)²= 3.734 X 10∧-14m²

Speed = 3.734 X 10∧-14m²/(6 X 10∧-8)m²/s = 0.0622ns