What is the area pf a cross section 12 units from the center of a sphere with a radius of 13?

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Answer 1 · 2017-07-28T08:02:00

1st part

Let the radius of the circular cross section 12 units apart from the center of a sphere with a radius of 13 be #r#

Then #r^2=13^2-12^2=25#

So the required area of cross section

#A=pir^2=pixx25=25pi# sq.unit

2nd part

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Given

Height #BE=24 # inch

Radius #AB=8# inch

And #CE=6# inch

Using the ptoperty of similar triangle we can write

#(CD)/(AB)=(CE)/(BE)#

#=>(CD)/8=6/24#

#=>CD=6/24xx8=2# inch

So required area of cross section will be

#"area"=pixxCD^2=pixx2^2=4pi# sqinch