Cylinder a has a radius 2 cm and contains water to a height of 10cm cylinder b has a radius 5cm and is empty. Some of the water is poured from cylinder a to b the height is now the same

Respuesta :

Answer:

h = 1.38 cm

Step-by-step explanation:

The question is at what value is the height of both cylinders the same:

The area of the circular base on each cylinder is:

[tex]Area=\pi r^2\\A=4\pi \ cm^2\\B=25\pi \ cm^2[/tex]

The initial volume in cylinder A is:

[tex]V=4\pi *10\\V=40\pi\ cm^3[/tex]

We have that Va + Vb = 40π. The height of water in each cylinder as a function of volume is:

[tex]h_A=\frac{V_a}{4\pi}\\h_B=\frac{V_b}{25\pi}[/tex]

If both heights are the same:

[tex]\frac{V_a}{4\pi}=\frac{V_b}{25\pi}\\V_b=\frac{25}{4}V_a \\V_a+V_b=40\pi\\V_a+\frac{25}{4}V_a=40\pi\\V_a=5.5172\pi\ cm^3[/tex]

The height 'h' is:

[tex]h=\frac{5.5172\pi}{4\pi}\\ h=1.38\ cm[/tex]