Question

You need to fill a basketball with air to play with it. You know that your pump expels air at a velocity of 6 cm/s. You know that the volume flow rate of air being pumped into the basketball is 103 cm^3/s. What is the diameter of your needle?

Answer 1

Answer:Volume flow = Area of cross section*velocity

So, volume of air flow= area of cross section*velocity of air flow

103=(pi*D*D/4)*6

D = 4.67cm

Explanation:

Answer 2

Answer:

4.67 cm

Explanation:

Q=V*A

Q=103 cm^3/s

V=6 cm/s

A=$\pi$$\frac{1}{4\\}$$d^{2}$

substitutes the values and you get

103 cm^3/s=6 cm/s*($\pi$$\frac{1}{4\\}$$d^{2}$)

clear "d" and you get

d=$\sqrt{\frac{Q}{V*\frac{1}{4} d} }$

d=4.67 cm