.The bases of a hemisphere and a cone are equal. If their heights are also equal then ratio between their curved surface area is—
(a) 1 : √2
(b) √2 ∶1
(c) 1 : 2
(d) 2 : 1
(e) None of these

• 
  GIVEN: both having same radius and the heights are same. So height of cone is same as the radius.
  
  2πr^2 / πrl
  2r/√(r^2+h^2) , where πr gets cancelled on both sides and l^2=r^2+h^2
  2r/√(2r^2) , r=h
  2/√2
  √2/1
  ans: (B) √2 ∶1
• 7 years agoHelpfull: Yes(9) No(1)
• 2πr^2 / πrl where l=√2 r
• 7 years agoHelpfull: Yes(0) No(1)
• b
  2pir2/pirl
  
• 7 years agoHelpfull: Yes(0) No(0)
• Curved Surface Area = πrl
  Curved surface area of a hemisphere=2πr2
  so option (b) is CORRECT
• 7 years agoHelpfull: Yes(0) No(0)
• Curved Surface area of cylinder is 2πr×l
  Curved Surface area of cone is πr×L
  So ratio is 2:1
• 6 years agoHelpfull: Yes(0) No(0)