if the hight of a cylinder is 4 inches, and the volume is 15 ml, whats the diameter?

please answer asap! its so important!

if the hight of a cylinder is 4 inches, and the volume is 15 ml, whats the diameter?

please answer asap! its so important!

Tutors, please sign in to answer this question.

Miami, FL

V=(∏D^{2}/4)*h

Plugging all the data in the above formula, we obtain:

15=(∏D^{2}/4)*4*2.54

D^{2}= 1.90 cm

D= 1.38 cm

D= 0.54 inches

For 10 ml D^{2}will be 1.2666

D will be 1.1254 cm and

D= 0.443 inches

for the 20Ml D^{2} = 2.532

Orlando, FL

Zack,

1st of all we need to get everything into a consist system of units. For the volume V = 15 mL,

one mL = 1 cm ^{3 }, so rather than try to convert this to cubic inches lets work with cm since the conversion from inches to cm is straight forward. 1 inch = 2.54 cm, so 4 inches x 2.54 cm per inch = 10.16 cm.

Now for a cylinder, volume = height (h) x area of the base (pi*radius squared).

so V = h*pi*r²

To find r we rearrange: r² = V/(h*pi) , so r = [V/(h*pi)]^{½ }

and d = 2*r

Solving for r we get r = [15 cm^{ 3} /(10.16 cm * 3.14)] ^{½ }= 0.69 cm

then d = 2*r =1.4 cm

Let's check our result. V = h*pi*r² , so V = 10.16 cm * pi * (0.69 cm)² = 15.2 cm^{³} ,

so we're right back where we started within round off errors.

Now if you like you can convert d = 1.4 cm back to inches : 1.4 cm / 2.54 cm per inch = 0.55 inches

Thanks a lot. your awesome!

what would be the answer if the ml was 10, and 20??

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## Comments

^{3}, I already fixed it, thanks to the tutor.what would be the answer if the ml was 10, and 20??