A joker 's cap is in the form of a right circle cone of base radius 7cm and height 24cm. Find the area of the sheet required to make 10 such caps.
Let l be the slant height of the cap.
Given:-Radius of cap (r)=7cm
Height of cap (h)=24cm
Therefore,
l2=h2+r2
⇒l2=(24)2+(7)2
⇒l2=576+49
⇒l=√625=25
Now,
Curved surface area of cap = Curved surface area of cone
As we know that,
Curved surface area of cone =πrl
Therefore,
Curved surface area of cap =227×7×25=550cm2
Now,
C.S.A. of 1 cap =550cm2
C.S.A. of 10 caps =550×10=5500cm2
Thus the area of the sheet required to make 10 such caps is 5500cm2.
Hence the correct answer is 5500cm2.