How Large is the Spherical Cavity Inside the Concrete Chunk?

Thread starter wallace13
Start date Jan 14, 2009

AI Thread Summary

The discussion focuses on calculating the radius of a hollow spherical cavity within a concrete chunk weighing 34 kg and having a total volume of 0.035 m³. Using the density of concrete (2200 kg/m³), the volume of the concrete itself is determined to be approximately 0.01545 m³. Subtracting this volume from the total volume gives a cavity volume of about 0.01955 m³. Applying the formula for the volume of a sphere, the radius of the spherical cavity is calculated to be approximately 0.167 m. The calculations are confirmed to be accurate.

Jan 14, 2009

wallace13

An irregularly shaped chunk of concrete has a hollow spherical cavity inside. The mass of the chunk is 34 kg, and the volume enclosed by the outside surface of the chunk is 0.035 m3. What is the radius of the spherical cavity?

D=m/v
4/3 pi r^3= volume of a sphere

2200 kg/ m cubed (density of concrete)= 34 kg/ v
V= .01545
.035-.01545= .01955
.01955= 4/3pi r^3
r=.167 m

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Jan 14, 2009

LowlyPion

Homework Helper

Looks OK.

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